US20070020115A1

US20070020115A1 - Integrated pump apparatus for semiconductor processing

Info

Publication number: US20070020115A1
Application number: US11/173,962
Authority: US
Inventors: Graeme Huntley; Neil Bellenie; Peter Holland; Michael Percy; Richard Lewington; David Wong
Original assignee: BOC Group Inc
Current assignee: Edwards Vacuum LLC
Priority date: 2005-07-01
Filing date: 2005-07-01
Publication date: 2007-01-25

Abstract

The invention relates to an integrated pump apparatus for use in semiconductor processing. The apparatus may include a turbomolecular pump and a dry pump positioned no more than about 20 centimeters away from each other. The turbomolecular pump and dry pump may share at least one of a common housing and a common controller. The apparatus may also include at least one of an abatement device and a cryogenic water pump.

Description

FIELD OF THE INVENTION

BACKGROUND OF THE INVENTION

Semiconductor wafers are used to form a number of different types of devices. For example, wafers, or portions of wafers, may be used to form memory devices, microprocessor unit devices, or combinations of the two devices. The devices may be very small, (e.g., on the order of only one Micron), and thus these devices are often manufactured in large batches. In some instances, a single wafer may have hundreds of devices manufactured on it.
In order to manufacture a device on a wafer, a number of discrete steps are performed. Although the number of steps may vary greatly depending on the type and complexity of the device, a typical manufacturing process may include anywhere between 100 and 300 individual steps between the initial step of providing an initial substrate and the finals step of extracting individual devices from the wafer and installing them in personal computers, telephones, mobile phones, or other electronic equipment.
Some of the steps in semiconductor wafer processing may include etching away selected material, depositing selected materials, and performing selective ion implantation in the silicon wafer. Many of these steps are performed by tools especially designed for the particular step, but several steps may also be performed by a single tool. Because these steps may be performed in a variety of locations, the wafer may often be moved. For example, the wafer may be placed in and taken out of ion implanter tools, transported by cassettes, placed in and taken out of deposition tools, and placed in and taken out of etch tools, etc.
As mentioned above, etching is one form of processing that may be performed on a wafer. The wafer may be etched a number of different times at a number of different levels for a number of different reasons. For example, one type of etching step includes placing a photoresist type material over an area of the wafer. The photoresist on the wafer may be then be exposed to a light source with a specific wavelength and a specific pattern. The exposure of the photoresist to the light source may alter the chemical composition of the exposed area such that the photoresist either “hardens” so that when a chemical is applied the “hardened” photoresist remains, or “softens” so that when a chemical is applied the “softened” photoresist is removed. In either case, a desired photoresist pattern remains on the wafer. Using this remaining photoresist as a mask, chemical substances may be applied to the wafer so as to etch away or remove exposed portions of the wafer. Thus, a desired pattern may be “etched” into the silicon wafer.
The devices and/or patterns that are etched into the wafer often have dimensions that are on the order of one micron. Because the dimensions being dealt with are so small, etching processes are especially susceptible to contaminants. For example, foreign molecules may become lodged in the channels etched into the wafers, and the existence of such flaws may prevent a device or portions of the device from working properly. Accordingly, in order to minimize these flaws, much attention is paid to the method by which the etching is performed, specifically by working to minimize the number of contaminants in the system.
The most common method of controlling the etching is by etching in a vacuum chamber using a plasma. The vacuum chamber is, by definition, kept at a low pressure, for example, between pressures of about 10⁻³millibar and about 10⁻¹millibar. The plasma used to etch the wafers may include the addition of any number of substances, such as fluorocarbons or perflourocarbons, which within the plasma may be broken up into smaller portions, such as fluorine and fluorine radicals. These smaller portions react with the exposed portions of the wafer and “etch away” that portion of the wafer through the formation of volatile reactant by-products. Other substances may be used depending on the substrate to be etched. Performing this procedure under vacuum substantially prevents contaminants from entering the system, as the chemicals present are normally only those specifically introduced into the system and the reduced pressure may moderate the reaction rate as the molecular density may be lower.
In a number of current etching procedures, a large number of reactants are run past the wafer at high speeds, for example, on the order of thousands of liters per second. This runs contrary to the desire to minimize the number of contaminants by keeping the pressure in the vacuum chamber low. What results is a desire to pass etching substances through the vacuum chamber at high speeds, but low pressures, and thus specialized pumps are often desired.
Currently, there are two discrete, completely separate, unintegrated pumps used in conjunction with each other to provide a high flow rate of etching substance at low pressures. The pumps have, among things, separate housings, separate controllers, separate electrical connections, and separate fluid connections, and are located long distances away from one another in different rooms of a wafer processing facility.
In some current configurations, an inlet of a first pump is bolted to the bottom of the vacuum chamber and receives the substances from the vacuum chamber that are flowing at the low pressures. The first pump then gradually increases the pressure of the substance flow from the molecular level (at the inlet) to about the transition level (at the outlet). The substance flow is then sent through a tube or pipe to a second pump which is located in another room, for example, a basement of the wafer processing facility. The second pump is currently located in another room of the wafer processing facility for several reasons, most prominent of which are its size, the amount of noise it generates, and its maintenance. The flow path (e.g. tube) connecting the pumps is typically between 5 and 15 meters in length, with a minimum length of 3 meters and a maximum length of 20 meters. The second pump gradually increases the pressure of the substance flow from about the transition level (at the inlet) to about atmospheric pressure (at the outlet). The second pump then exhausts the substance flow.
There are some drawbacks associated with the current dual pump arrangement. For example, having the second pump in a room separate from the first pump is often an inefficient use of space. In addition, there are efficiency losses associated with flowing the substances through a long tube connecting the pumps. Accordingly, alternative arrangements and/or configurations of multiple pumps are desired.

SUMMARY OF THE INVENTION

In the following description, certain aspects and embodiments of the invention will become evident. It should be understood that the invention, in its broadest sense, could be practiced without having one or more features of these aspects and embodiments. It should also be understood that these aspects and embodiments are merely exemplary.
One aspect, as embodied and broadly described herein, may relate to an apparatus for use in semiconductor processing. The apparatus may include a turbomolecular pump and a dry pump, and the turbomolecular pump and the dry pump may be coupled together so as to position the turbomolecular pump and the dry pump no more than about 20 centimeters from one another.
In a further aspect, an apparatus for use in semiconductor processing may include a turbomolecular pump and a dry pump coupled to the turbomolecular pump. The apparatus may include at least one of a common housing associated with both of the pumps and a common controller associated with both of the pumps.
Still another aspect may relate to an apparatus that may include a turbomolecular pump, a dry pump coupled to the turbomolecular pump, and a semiconductor processing tool associated with the turbomolecular pump and the dry pump. The turbomolecular pump, the dry pump, and the semiconductor processing tool may be disposed in a single room of a facility where semiconductors are processed.
Various aspects may include one or more optional features. For example, the turbomolecular pump and the dry pump may be coupled together so as to position the turbomolecular pump and the dry pump no more than about 10 centimeters from one another; the turbomolecular pump and the dry pump may be coupled together so as to position the turbomolecular pump and the dry pump no more than about 0.5 centimeters from one another; the apparatus may include at least one of a common housing associated with both of the pumps and a common controller associated with both of the pumps; the apparatus may include a semiconductor processing tool associated with the turbomolecular pump and the dry pump; the turbomolecular pump, the dry pump, and the semiconductor processing tool may be disposed in a single room of a facility where semiconductors are processed; the boundary between the turbomolecular pump and the dry pump may not be externally discernable; the apparatus may include only one electrical connection configured to provide electrical power input to both of the pumps; the apparatus may include only one fluid connection configured to provide fluid to at least one of the pumps; the apparatus may include only one cooling water connection configured to provide cooling water to at least one of the pumps; the apparatus may include only one nitrogen connection configured to provide nitrogen to at least one of the pumps; the apparatus may include only one clean dry air connection configured to provide clean dry air to at least one of the pumps; the apparatus may include a common controller; the common controller may control both the turbomolecular pump and the dry pump; the apparatus may include a cryogenic water pump; the common controller may be associated with the cryogenic water pump; the common controller may control the turbomolecular pump, the dry pump, and the cryogenic water pump; the apparatus may include an abatement device; the common controller may be associated with the abatement device; and the common controller may control the turbomolecular pump, the dry pump, and the abatement device.
Aside from the structural relationships discussed above, the invention could include a number of other forms such as those described hereafter. It is to be understood that both the foregoing description and the following description are exemplary only.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of this specification. The drawings illustrate several embodiments of the invention and, together with the description, serve to explain some principles of the invention. In the drawings:
FIG. 1 is a schematic view of an embodiment of an apparatus in accordance with the present invention;
FIG. 2 is a schematic view of another embodiment of the apparatus;
FIG. 3 is a schematic view of a further embodiment of the apparatus;
FIG. 4 is a schematic view of yet another embodiment of the apparatus;
FIG. 5 is a schematic view of a further embodiment of the apparatus;
FIG. 6 is a schematic view of still another embodiment of the apparatus;
FIG. 7 is a schematic view of a still further embodiment of the apparatus;
FIG. 8 is an exploded perspective view of part of the apparatus of FIG. 6;
FIGS. 8A and 8B are perspective views of portions of yet another embodiment of the apparatus;
FIGS. 8C and 8D are schematic views of the portions of FIGS. 8A and 8B;
FIG. 9 is a schematic view of a yet further embodiment of the apparatus; and
FIG. 10 is a schematic view of yet another embodiment of the apparatus.

DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to some possible embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.
FIGS. 1-8 depict exemplary embodiments of an apparatus for use in semiconductor processing. The apparatus 1 may include a turbomolecular pump 10 and a dry pump 30.
The turbomolecular pump 10 may be a pump configured to provide turbomolecular flow of a substance such that molecules of the substance are more likely to collide with at least one interior wall 15 (FIGS. 1 and 2) of the pump rather than into other substance molecules. The turbomolecular pump 10 may have an inlet 11 to receive a flow of the substance at a first pressure and an outlet 12 to expel the substance flow at a second pressure. As shown in FIG. 2, the turbomolecular pump 10 may include blades 13 that rotate together to transition substance flow from an input pressure on the order of about 10⁻¹to 10⁻³millibar (e.g., such as when the input flow passing through inlet 11 is from an etching tool) or less (e.g., a pressure as low as about 10⁻⁸millibar, such as, for example, when the input flow passing through inlet 11 is from a tool or other structure associated with an application other than etching, for example, physical vapor deposition (“PVD”) to an output pressure on the order of about 1 to 10 millibar. The blades 13 may be disposed in the turbomolecular pump 10 using mechanical bearings, or the blades 13 may be magnetically levitated within the turbomolecular pump 10. The blades 13 may also be connected by a central shaft. For example, as shown in FIG. 10, blades 13 may be disposed on a shaft 113. A top portion of shaft 113 closer to inlet 11 may be suspended by magnetic bearings, and a bottom portion of shaft 113 closer to outlet 12 may be suspended by mechanical bearings. In various embodiments, however, shaft 113 may be suspended by any number of bearings of any type and in any combination (e.g., two mechanical bearings or two magnetic bearings).
Adjacent blades 13 may be spaced from one another by an intervening stator 14. The stators 14 may remain substantially stationary during the pumping process, and may be fixed to an outer cylinder that surrounds the blades 13.
The molecules entering the pump 10 may have a substantially random motion. These molecules may then land on a rotating blade 13 and pick up the blade's 13 velocity such that on leaving the blade 13, the molecule has the velocity of the blade 13 as well as the blade's intrinsic thermal velocity. Thus, compression may be generated by a combination of blades 13 providing a higher transmission probability downwards rather than upwards due to the angle of blades 13 and the relative blade velocity. Stationary stator 14 is also configured such that it generates compression through a combination of the relative gas velocity and the stator 14 providing a higher transmission probability downwards as compared to upwards due to the angle of the stator blade. The stator 14 may have a relative velocity from the reference of the molecule such that equal pumping may be provided by stator 14 and blade 13.
Additional details concerning exemplary configurations of a turbomolecular pump 10 with blades 13 and stators 14, and its various components, are set forth in U.S. Pat. Nos. 6,109,864 and 6,778,969, which are both incorporated herein by reference in their entirety.
Each of the blades 13, intervening stators 14, and/or other portions of the turbomolecular pump 10 may be configured to efficiently move substances at low pressures. Turbomolecular pumps typically operate with inlet pressures between 10⁻¹millibar to 10⁻⁸millibar and corresponding outlet pressures from 10 millibar to 1 millibar or less depending on flow and the size of the pump downstream. One or more of blades 13 and intervening stators 14 may rotate at relatively high speeds, for example, up to twenty-thousand revolutions-per-minute or more.
The turbomolecular pump 10 may include a molecular drag portion 17. The molecular drag portion 17 may be disposed before and/or after the blades 13 and stators 14. The molecular drag portion 17 may include two co-axial hollow cylinders 18, 19. One or more of the cylinders 18, 19 may have a helical thread 20 provided on the surface facing the other cylinder 18, 19. In operation, one or more of the cylinders 18, 19 may rotate at relatively high speeds, for example, up to twenty-thousand revolutions-per-minute or more. Accordingly, at low pressures the molecules may strike the surface of the rotating helical thread 20, giving the molecules a velocity component and tending to cause the molecules to have the same direction of motion as the surface against which they strike. The molecules may be urged through the molecular drag portion 17 in this manner and exit the molecular drag portion 17 at a higher pressure than that at which they entered. Further details regarding exemplary molecular drag portions and their various components can be found in U.S. Pat. No. 5,772,395, which is incorporated herein by reference in its entirety.
Molecular drag portion 17 may have an alternate configuration, for example, as shown in FIG. 9. Molecular drag portion 17 may have several stationary cylinders 18 having a helical thread 20 and several rotating cylinders 19. Rotating cylinders 19 may be connected, may rotate at substantially the same rotational speed, and/or may be disposed on the same shaft 113 as blades 13. Each stationary cylinder 18 and surface of rotating cylinder 19 facing its respective stationary cylinder may comprise a separate molecular drag portion 17. Some molecular drag portions 17 may include a surface of a stationary cylinder 18 having a helical thread 20 facing radially outward and also facing a substantially flat radially inward surface of a rotating cylinder 19. Some molecular drag portions 17 may have the opposite configuration. Each stationary cylinder 18 may have helical threads 20 on its radially outward surface and/or its radially inward surface. Each rotating cylinder 19 may face a surface of a stationary cylinder 18 having helical threads 20 on its radially outward surface and/or its radially inward surface.
Each molecular drag portion 17 may be in flow communication with other molecular drag portions 17. Each molecular drag portion 17 may be disposed radially inward or outward from other molecular drag portions 17. Each molecular drag portion 17 may have a different configuration. For example, the helical threads 20 in each molecular drag portion 17 may have a different length than helical threads 20 in other molecular drag portions 17. Molecular drag portions 17 may be disposed radially outward from turbomolecular pump 10. Each molecular drag portion 17 may be configured to increase a pressure of the substance while the substance flows through the molecular drag portion 17, and then exhaust the substance to a more radially outer molecular drag portion 17 until the substance is exhausted by the final molecular drag portion 17 to the dry pump 30.
The dry pump 30 may be a pump configured to provide transition flow and/or viscous flow of the substance such that molecules of the substance are more likely to collide with each other rather than at least one interior wall 35 (FIG. 1) of the pump. The dry pump 30 may have an inlet 31 to receive a substance flow at a first pressure and an outlet 32 to expel the substance flow at a second pressure. One exemplary type of dry pump 30 may include rotating blades 33 (FIG. 2), typically having a different geometry than those of a turbomolecular pump, such that they are suitable for operating at higher pressures with intervening stators 34 which may be configured to transition substance flow from an input pressure on the order of about 1 to 10 millibar or less (e.g., a pressure as low as about 0.1) to atmospheric pressure on the order of about 1000 millibar. The blades 33 may be disposed in the dry pump 30 using bearings, and/or the blades 33 may be disposed on a rotary shaft. The stators 34 may be fixed to a cylindrical housing that surrounds the blades 33. The blades 33 and stators 34 may operate similar to the blades 13 and stators 14 described above with respect to turbomolecular pump 10, in that the dry pump 30 may cause an increase in the pressure of the substance passing into the dry pump 30 via the inlet 31 before the substance exits the dry pump 30 via the outlet 32. Examples of dry pumps and their various components are disclosed in U.S. Pat. Nos. 6,244,841, 6,705,830, 6,709,226, 6,755,611 B1, which are all incorporated herein by reference in their entirety. Other suitable examples of dry pumps include a screw pump as disclosed in U.S. Pat. Nos. 6,129,534, 6,200,116, 6,379,135, and 6,672,855, which are incorporated herein by reference in their entirety.
Dry pump 30 may have an alternate configuration, for example, as shown in FIGS. 8A, 8B, 8C, 8D, and 9. In the alternate configuration, dry pump 300 may include a regenerative rotor 350 and a regenerative stator 370.
As shown in FIG. 8A, regenerative rotor 350 may include a plurality of substantially circular protrusions 351 extending from a surface of regenerative rotor 350. Protrusions 351 may have a plurality of blades 352 extending therefrom. A cross-section of protrusion 351 and blade 352 is shown in FIG. 8D.
As shown in FIG. 8B, regenerative stator 370 may include a plurality of protrusions 371 defining a plurality of channels 372 therebetween. Adjacent channels 372 may be connected via intervening channels 373. A cross-section of protrusion 371 and channel 372 is shown in FIG. 8D. Each channel 372 may include a first portion 372 a and a second portion 372 b. First portion 372 a may be slightly wider than a width of protrusion 351, for example, to prevent the flow of a substance therebetween. Thus, in operation, any substance may be substantially contained in second portion 372 b. Second portion 372 b may have any suitable cross-sectional shape to accommodate substance flow, for example, a curved or oval-like shape.
As shown in FIGS. 8C and 9, each blade 352 may be placed in one of channels 372 such that protrusion 351 is disposed in first portion 372 a, and that blade 352 extends into second portion 372. Each set of blades 352 and channels 372 may include a corresponding inlet 391 and outlet 392 which may or may not be the same as intervening channels 373.
In operation, blade 352 may rotate relative to channel 372. A substance may enter second portion 372 b of channel 372 via inlet 391. Blade 352 may then cause the substance to flow in the same direction as the rotation of blade 352, for example, in a substantially oval-like and/or spiral-like pattern. The substance may then exit second portion 372 b of channel 372 via outlet 392. The substance may then be sent to another blade 352 and channel 372 combination, or may be exhausted from pump 1.
As shown in FIG. 9, dry pump 30 may have a plurality of blade 352 and channel 372 combinations. Each combination of blades 352 and channels 372 may be disposed radially inward and/or outward from other combinations of blades 352 and channels 372. Rotor 350 may be disposed on the same shaft 106 as blades 104 and cylinders 202. Each combination of blades 352 and channels 372 may exhaust the substance from an outer combination to a combination disposed radially inward. The inner-most combination may exhaust the substance out of the pump 1, for example, to the atmosphere.
In some examples, the turbomolecular pump 10 may be coupled to the dry pump 30 such that the turbomolecular pump 10 and the dry pump 30 are positioned no more than about 20 centimeters from one another. In such a configuration, the outlet 12 of the turbomolecular pump 10 may be connected to the inlet 31 of the dry pump 30 such that the outlet 12 and inlet 31 are in flow communication with each other so as to pass the substance pumped from the turbomolecular pump 10 into the dry pump 30.
In one exemplary embodiment, as shown in FIG. 1, the outlet 12 of the turbomolecular pump 10 may be connected to the inlet 31 of the dry pump 30 by a tube 50 that is no more than 20 centimeters in length. In some examples, the tube 50 may have a length of less than about 20 centimeters. For example, the length may be less than about 10 centimeters or less than about 0.5 centimeters.
In another exemplary embodiment, as shown in FIG. 2, the turbomolecular pump 10 may be directly connected to the dry pump 30 such that the outlet 12 of the turbomolecular pump 10 directly contacts the inlet 31 of the dry pump 30. In such an embodiment, the distance between the end of the blade 13 immediately preceding the outlet 12 of the turbomolecular pump 10 and the beginning of the blade 33 immediately following the inlet 31 of the dry pump 30 may be no more than about 20 centimeters. In various embodiments, the distance between pumping elements 13, 33 may be less than about 20 centimeters, less than about 10 centimeters, or less than about 0.5 centimeters.
As shown in FIGS. 1 and 2, the turbomolecular pump 10 and the dry pump 30 may share a common housing 80 and the boundary between the two pumps may not be externally discernable (i.e., a person viewing the exterior of the apparatus with unassisted vision would not be able to visualize the boundary between the pumps 10 and 30). Each of the pumps 10, 30 may have its own respective driving motor so as to rotate the sets of blades or other mechanism 13 and 33 at different speeds.
FIGS. 4-7 depict exemplary embodiments of apparatuses 1 each including an abatement device 60. The abatement device 60 may be configured to convert a substance gas flow, which may be at least partially toxic and/or chemically volatile, and/or include a global warming gas, etc., into a form that is more manageable, stable, and/or benign. Some examples of different types of abatement devices 60 include plasma-type abatements, burning type abatements, abatements with electrically heated surfaces, etc.
In one example of an abatement process, the abatement device 60 may receive a substance flow including perfluorocarbons (“PFCs”) via at least one of the turbomolecular pump 10 and the dry pump 30. The abatement device 60 may then take the PFCs and break them up into hydrogen flouride (“HF”). While HF may be more hazardous than PFCs, unlike PFCs, HF may be readily dissolved in water. Thus dissolved, the HF may now be more easily handled and/or disposed. More details concerning this type of abatement is disclosed in U.S. Pat. No. 6,530,977, which is incorporated herein by reference in its entirety.
Another example of abatement device 60 is disclosed in U.S. Pat. No. 6,358,485, which is incorporated herein by reference in its entirety. In such an abatement device, a gas stream containing trimethylvinylsilane (TMVS) is exposed to a gas stream containing copper oxide and/or manganese oxide, which chemically combine to form a non-toxic byproduct. This non-toxic byproduct may then be readily and more easily disposed.
In another example of an abatement process, the abatement device 60 may receive a substance flow including fluorine via at least one of the turbomolecular pump 10 and the dry pump 30. The abatement device 60 may take the fluorine and burn it (or otherwise heat it and provide a hydrogen atom source) so as to form HF. The HF may then be dissolved in water and disposed of.
In yet a further example of an abatement process, the abatement device 60 may receive a substance flow including pyrophoric gas(es) (e.g., silane) via at least one of the turbomolecular pump 10 and the dry pump 30. The abatement device 60 may take the pyrophoric gas(es) and mix it with air heated to at least 300 degrees Celsius. Such mixing may reduce the amount of pyrophoric gas(es) that exits the abatement device, thus making the substance flow safer and easier to handle. More details concerning an example of this type of abatement are disclosed in U.S. Pat. No. 6,530,977, which is incorporated herein by reference in its entirety.
The abatement device 60 may be positioned at any location so as to receive substance passing to, or flowing from, either or both of the pumps 10, 30. If the abatement device 60 operates more efficiently at lower pressures, the abatement device 60 may be positioned downstream from the turbomolecular pump 10 and upstream from the dry pump 30, as shown in FIG. 5. If the abatement device operates more efficiently at higher pressures the abatement device 60 may be positioned downstream from both of the turbomolecular pump 10 and the dry pump 30, as shown in FIGS. 4, 6, and 7.
FIGS. 5 and 7 depict exemplary embodiments of an apparatus 10 including a cryogenic water pump 70. The cryogenic water pump 70 may be configured to receive the substance flow from a vacuum processing chamber 2 (partially shown in FIG. 5 in schematic form) and remove water at a very high efficiency. It may also be used to remove from the substance flow other desired material(s), such as lower vapor pressure precursors used within the semiconductor process (although in some example, it may possibly be more desirable to pump such materials through the turbomolecular pump and drypump.
In some examples, the vacuum processing chamber 2 may be associated with a semiconductor wafer processing arrangement where very low levels of water vapor may be used and/or created. For example, when a vacuum is created in the vacuum processing chamber 2, water molecules may be collected on the inner surfaces of the chamber 2. When the substance flow exits the vacuum chamber 2, it may be desirable to substantially prevent any of the water vapor from reentering the vacuum processing chamber 2.
The cryogenic water pump 70 may remove the water vapor from the substance flow by causing the water vapor to freeze and become trapped on cryogenically cooled surfaces of the cryogenic water pump 70. If the temperature of the surfaces of the cryogenic water pump 70 is lowered enough, the cryogenic water pump 70 may also trap other materials on its surface, for example lower vapour pressure precursors used within the semiconductor process. If the temperature is lowered further, then gases like carbon dioxide and argon may be trapped, although these gases may be more commonly handled downstream from the turbomolecular pump and/or the dry pump. Avoiding oxygen condensation may also be desirable, hence the use of a cryogenic pump for water but turbomolecular pump for gases.
As shown in FIGS. 5 and 7, the cryogenic water pump 70 may be mounted onto the top of the turbomolecular pump 10 such that an outlet of the cryogenic water pump 70 ends where the inlet of the turbomolecular pump 10 begins. In other examples, the top section of the turbomolecular pump 10 may house the cryogenic water pump 70 such that the cryogenic water pump 70 is not externally discernable. In some examples, there may be a valve between the two pumps 30, 70.
FIGS. 6-8 depict exemplary embodiments of an apparatus 1 with common portions and/or connections. The common housing 80 may be associated with both the turbomolecular pump 10 and the dry pump 30. The common housing 80 may also be associated with the abatement device 60 and/or the cryogenic water pump 70. The common housing 80 may be configured such that the boundaries between the turbomolecular pump 10, the dry pump 30, the abatement 60, and/or the cryogenic water pump 70 are not externally discernable.
As shown in FIG. 7, the turbomolecular pump 10, the dry pump 30, the abatement device 60, and/or the cryogenic water pump 70 may be disposed in a single room 3 of a semiconductor processing facility.
As shown in FIGS. 6 and 7, the turbomolecular pump 10, the dry pump 30, the abatement device 60, and/or the cryogenic water pump 70 may have a common controller 90 that controls each of the turbomolecular pump 10, the dry pump 30, the abatement 60, and/or the cryogenic water pump 70. The common controller 90 may be connected to the turbomolecular pump 10, the dry pump 30, the abatement 60, and/or the cryogenic water pump 70 by a controller connection 91.
In some examples, rather than having a wired connection, a wireless link may provide communication between the common controller 90 and the turbomolecular pump 10, the dry pump 30, the abatement 60, and/or the cryogenic water pump 70.
The turbomolecular pump 10, the dry pump 30, the abatement 60, and/or the cryogenic water pump 70 may share common connections. For example, the turbomolecular pump 10, the dry pump 30, the abatement 60, and/or the cryogenic water pump 70 may share a common power connection 100 (FIG. 6). The power connection 100 may provide electrical power to the turbomolecular pump 10 and the dry pump 30 so as to power motors associated with the respective mechanisms of the turbomolecular pump 10 and the dry pump 30. This connection may also be fed through the remote controller cabinet 90 to condition power before being directed to the turbomolecular pump 10 and the dry pump 30.
As shown in FIG. 8, the turbomolecular pump 10 and the dry pump 30 may share common water distribution route 101. As the turbomolecular pump 10 and the dry pump 30 operate, they generate heat due to compression of the substance (e.g., when the substance is a gas) and cause the substance flow in the pumps 10, 30 to increase in temperature. In order to moderate the temperature of each of the pumps 10, 30, water may be introduced into, circulated through, and removed from the pumps 10, 30 so as to remove heat. In an exemplary embodiment, water may enter at least one of the pumps 10, 30 via one of the common water distribution route 101 at about 20° C. and leave at least one of the pumps at about 30-35° C. via the other water distribution route 101.
The turbomolecular pump 10 and the dry pump 30 may share a common nitrogen distribution route 102. Nitrogen may be used to protect certain elements of the pumps 10, 30 from contamination. For example, the pumps 10, 30 may each have a motor and bearing arrangement, and the nitrogen may be used to keep potentially corrosive process materials away from the bearings or other portions in the motors of the pumps 10, 30.
Nitrogen may additionally (or alternatively) be used to dilute gas flowing through at least one of the pumps 10, 30. For example, if a very light gas, such as hydrogen or helium, is being pumped through the pumps 10, 30, the light gas may move around very quickly, and thus may have a tendency to flow undesirably backwards through the turbomolecular pump 10 and the dry pump 30. By adding nitrogen, the density of the chemical flow may be increased and the backwards flow of the light gas species may be substantially reduced and/or eliminated.
Nitrogen may additionally (or alternatively) be used to substantially prevent condensation within at least one of the pumps 10, 30. For example, water may condense out of the substance flow as the substance flow is brought up to atmospheric pressure. By adding nitrogen to the substance flow, the water within the substance flow passing through at least one of the pumps 10, 30 may be diluted, and thus condensation of the water may be substantially limited or prevented by keeping the water in the vapor phase. In addition to limiting condensation of water, nitrogen may be used to limit condensation of other materials, such as, for example, silicon fluoride and silicon bromide.
Nitrogen may additionally (or alternatively) be used to dilute a flammable material so that it no longer has a flammable concentration.
As shown in FIG. 8, the turbomolecular pump 10 and the dry pump 30 may also share a common clean dry air (CDA) distribution route 103. The clean dry air may be substituted for nitrogen in some instances or be used to operate any pneumatic systems (e.g., valves).
The invention may have several advantages. For example, the invention may operate at a greater efficiency than pumps positioned at further distances relative to each other. In another example, conductance losses present during the use of pumps positioned at further distances relative to each other may be minimized and/or substantially eliminated, for example, due to a reduction in the length of the substance flow paths. In another example, the invention may take up less space than pumps positioned at further distances relative to each other and require less energy, important advantages in an industry where space and power consumption is at a premium. In a further example, because the exhaust from the apparatus may be greater than or equal to about 100 millibar, double containment of the apparatus may not be necessary as any sub-atmospheric leaks may be inwards.
It will be apparent to those skilled in the art that various modifications and variations can be made to the structure described herein. This, it should be understood that the invention is not limited to the subject matter discussed in the specification and shown in the drawings. Rather, the present invention is intended to include modifications and variations.

Claims

1. An apparatus for use in semiconductor processing, comprising:

a turbomolecular pump; and

a dry pump,

wherein the turbomolecular pump and the dry pump are coupled together so as to position the turbomolecular pump and the dry pump no more than about 20 centimeters from one another.

2. The apparatus of claim 1, wherein the turbomolecular pump and the dry pump are coupled together so as to position the turbomolecular pump and the dry pump no more than about 10 centimeters from one another.

3. The apparatus of claim 1, wherein the turbomolecular pump and the dry pump are coupled together so as to position the turbomolecular pump and the dry pump no more than about 0.5 centimeters from one another.

4. The apparatus of claim 1, wherein the apparatus comprises at least one of a common housing associated with both of the pumps and a common controller associated with both of the pumps.

5. The apparatus of claim 1, further comprising a semiconductor processing tool associated with the turbomolecular pump and the dry pump,

wherein the turbomolecular pump, the dry pump, and the semiconductor processing tool are disposed in a single room of a facility where semiconductors are processed.

6. The apparatus of claim 1, wherein a boundary between the turbomolecular pump and the dry pump is not externally discernable.

7. The apparatus of claim 1, wherein the apparatus includes only one electrical connection configured to provide electrical power input to both of the pumps.

8. The apparatus of claim 1, wherein the apparatus includes only one fluid connection configured to provide fluid to at least one of the pumps.

9. The apparatus of claim 1, wherein the apparatus includes only one cooling water connection configured to provide cooling water to at least one of the pumps.

10. The apparatus of claim 1, wherein the apparatus includes only one nitrogen connection configured to provide nitrogen to at least one of the pumps.

11. The apparatus of claim 1, wherein the apparatus includes only one clean dry air connection configured to provide clean dry air to at least one of the pumps.

12. The apparatus of claim 1, wherein the apparatus comprises a common controller, and wherein the common controller controls both the turbomolecular pump and the dry pump.

13. The apparatus of claim 1, wherein the apparatus comprises a common controller, wherein the apparatus further comprises a cryogenic water pump, and wherein the common controller is associated with the cryogenic water pump.

14. The apparatus of claim 13, wherein a common controller controls the turbomolecular pump, the dry pump, and the cryogenic water pump.

15. The apparatus of claim 1, wherein the apparatus comprises a common controller, wherein the apparatus further comprises an abatement device, and wherein the common controller is associated with the abatement device.

16. The apparatus of claim 15, wherein the common controller controls the turbomolecular pump, the dry pump, and the abatement device.

17. The apparatus of claim 1, wherein the apparatus comprises a common housing and a common controller.

18. An apparatus for use in semiconductor processing, comprising:

a turbomolecular pump; and

a dry pump coupled to the turbomolecular pump,

wherein the apparatus comprises at least one of a common housing associated with both of the pumps and a common controller associated with both of the pumps.

19. The apparatus of claim 18, wherein the apparatus comprises the common housing, and wherein the common housing includes only one electrical connection configured to provide electrical power input to both of the pumps.

20. The apparatus of claim 18, wherein the apparatus comprises the common housing, and wherein the common housing includes only one fluid connection configured to provide fluid to at least one of the pumps.

21. The apparatus of claim 18, wherein the apparatus comprises the common housing, and wherein the common housing includes only one water connection configured to provide water to at least one of the pumps.

22. The apparatus of claim 18, wherein the apparatus comprises the common housing, and wherein the common housing includes only one nitrogen connection configured to provide nitrogen to at least one of the pumps.

23. The apparatus of claim 18, wherein the apparatus comprises the common housing, and wherein the common housing includes only one clean dry air connection configured to provide clean dry air to at least one of the pumps.

24. The apparatus of claim 18, wherein the apparatus comprises the common controller, and wherein the common controller controls both the turbomolecular pump and the dry pump.

25. The apparatus of claim 18, wherein the apparatus comprises the common controller, wherein the apparatus further comprises a cryogenic water pump, and wherein the common controller is also associated with the cryogenic water pump.

26. The apparatus of claim 25, wherein the common controller controls the turbomolecular pump, the dry pump, and the cryogenic water pump.

27. The apparatus of claim 18, wherein the apparatus comprises the common controller, wherein the apparatus further comprises an abatement device, and wherein the common controller is also associated with the abatement device.

28. The apparatus of claim 27, wherein the common controller controls the turbomolecular pump, the dry pump, and the abatement device.

29. The apparatus of claim 18, wherein the apparatus comprises the common housing and the common controller.

30. The apparatus of claim 18, further comprising a semiconductor processing tool associated with the turbomolecular pump and the dry pump,

31. The apparatus of claim 18, wherein a boundary between the turbomolecular pump and the dry pump is not externally discernable.

32. An apparatus for use in semiconductor processing, comprising:

a turbomolecular pump;

a dry pump coupled to the turbomolecular pump;

a semiconductor processing tool associated with the turbomolecular pump and the dry pump,

33. The apparatus of claim 32, wherein the boundary between the turbomolecular pump and the dry pump is not externally discernable.

34. The apparatus of claim 1, wherein the turbomolecular pump and the dry pump share a common facility distribution path.

35. The apparatus of claim 18, wherein the turbomolecular pump and the dry pump share a common facility distribution path.