Classifications

• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
  • H10F77/00—Constructional details of devices covered by this subclass
  • H10F77/20—Electrodes
  • H10F77/206—Electrodes for devices having potential barriers
  • H10F77/211—Electrodes for devices having potential barriers for photovoltaic cells
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E10/00—Energy generation through renewable energy sources
  • Y02E10/50—Photovoltaic [PV] energy

Definitions

• the invention relates to a method for locally contacting a semiconductor component, which semiconductor component is part of a photovoltaic solar cell or a preliminary stage in the production process of a photovoltaic solar cell, according to the preamble of claim 1 and a processing table for carrying out such a method.
• charge carriers are typically dissipated by metal structures.
• metal structures are known which contact one side of the semiconductor component over the whole area.
• metal structures are used which have one or more local electrical contact areas to the semiconductor component.
• the semiconductor device consists of a semiconductor layer with a p-doped region and an n-doped region.
• the semiconductor layer may comprise additional insulating layers.
• the semiconductor component contacted locally by means of the metallic contacting structure is thus part of a photovoltaic solar cell or a preliminary stage of a photovoltaic solar cell in the manufacturing process, wherein the solar cell can have a plurality of semiconductor layers.
• a metal layer is applied over the entire surface, which thus covers the lift-off layer and covers the silicon substrate in the locally opened regions.
• a metal structure remains in the previously locally opened regions of the insulating layer on the surface of the silicon substrate.
• the present invention has for its object to provide a method for locally contacting a semiconductor device, the use of which improves the contact properties, in particular with respect to the electrical conductivity and adhesion, reduces the shading and which at the same time has a low Prozeßkompextician. Furthermore, the invention is intended to provide a machining table for carrying out such a method.
• the inventive method is used to produce a metal structure for local electrical contacting, d. H. a metallic contacting structure of a semiconductor device.
• the semiconductor component is a photovoltaic solar cell or a precursor of a photovoltaic solar cell in the manufacturing process and comprises at least one semiconductor layer. It is within the scope of the invention that the semiconductor layer is formed as a semiconductor substrate, in particular as a silicon wafer.
• the use of the method according to the invention in the production of front side contacts of a solar cell is advantageous in order to produce linear contacts with as little shading as possible, since the electromagnetic radiation is coupled into the semiconductor component via the front side.
• solar cells are contacted on the front side by line-like metallic contacting structures that are connected to one another like a comb.
• the method comprises the following method steps:
• At least one metal layer is applied to one side of the semiconductor component.
• a melting of at least the metal layer takes place in a local area for a short time.
• a metal foil is used as the metal layer and that in a method step C, the metal foil is removed in the areas not fused in method step B.
• the invention is based on the applicant's knowledge that by using a metal foil as the metal layer after the contacting step, the metal layer in the non-fused regions can be easily removed.
• the method according to the invention offers a cost-effective possibility of producing metal structures for local contacting of the semiconductor component.
• narrower structures with a higher aspect ratio (height to width of the metal structure) can be produced, so that further the use of silver is not absolutely necessary and thereby costs can be saved.
• commercially available metal foil for example, in a supermarket, commercially available metal foil can be used in the process according to the invention, which nevertheless has only a small thickness variation.
• At least one intermediate layer is applied to one side of the semiconductor component before method step A.
• This intermediate layer is particularly preferably a dielectric layer.
• the intermediate layer can be formed to increase the efficiency of the solar cell, in particular by forming the intermediate layer as a passivation layer in order to reduce the charge carrier recombination on the surface of the semiconductor layer and / or by forming the intermediate layer as an optical layer in order Reflection properties of the solar cell and thus improve the light absorption.
• an embodiment of the intermediate layer as a dielectric layer in particular as a silicon dioxide layer or silicon nitride layer is advantageous.
• the intermediate layer applied to one side of the semiconductor component is removed in the local regions. This results in the following Applying the metal foil these in the local contacting areas directly to the surface to be electrically contacted. This results in the advantage that a disturbance of the contact formation in the local melting of the metal foil is avoided by the material of the molten intermediate layer.
• the removal of the intermediate layer preferably takes place in such a way that the intermediate layer is ablated in the local regions by means of a laser and / or is removed by a wet-chemical etching process.
• a multilayer metal foil is used as the metal layer.
• This has the advantage that multistage metallic contacting structures with different properties in terms of conductivity, adhesion properties, material costs and / or contact resistance can be applied, and thus in particular a high conductivity can be achieved at a reduced cost.
• the metal layer is preferably locally heated by means of illumination, particularly preferably by means of a laser, in particular preferably by means of a pulsed laser.
• a laser having a wavelength in a range of 190 nm to 1 1 ⁇ , particularly preferably used with a length of 1 064 nm.
• a laser with a pulse length in the range of 10 ns to 1 0 s is used. It is also within the scope of the invention to use a laser in continuous wave mode (cw) or a cw laser in modulated mode for method step B. Investigations by the inventors have shown that the aforementioned parameters enable a smooth and error-free process flow.
• An advantage of the use of a laser for local heating and thus melting of the metal foil is that no determination of a given shape of the metal structure, for example, by a sieve used, as in the method according to the invention, the local melting at any location and with high Accuracy can take place.
• Titanium, silver, nickel, aluminum, tin, zinc and / or copper are preferably used as the material for the metal foil. Particularly preferred is for the Coating p-doped semiconductor materials used aluminum, nickel and / or titanium. Particular preference is given to using nickel, more preferably silver, preferably titanium, for the coating of n-doped semiconductor metal materials.
• the metal foil used to produce the metallic contacting structure of a semiconductor component preferably has a total thickness of more than 10 m, in particular if the entire metallic contacting structure is produced by means of the metal foil.
• a multilayer metal foil comprising a material suitable for contacting, a low-cost material with high conductivity and a material suitable for interconnecting the semiconductor component in the stated sequence.
• the individual layers preferably have thicknesses in the range between 100 nm to 10 m.
• the multilayer metal foils for producing a metallic contacting structure on a p-doped semiconductor component have the following structure:
• the multilayer metal foil on the side facing the semiconductor component comprises an approximately 100 nm thick nickel layer and / or titanium layer and / or aluminum layer.
• a middle layer of the multilayer metal foil may be made of a low-cost material that must have good conductivity, preferably copper or tin.
• the last layer of the multilayer metal foil on the side remote from the semiconductor component is a silver layer and / or tin layer and / or zinc layer and / or copper layer for further interconnection.
• the multilayer metal foils for producing a metallic contacting structure on an n-doped semiconductor component have the following structure:
• the multilayer metal foil on the side facing the semiconductor component comprises an approximately 100 nm thick nickel layer and / or titanium layer and / or silver layer.
• a middle layer of the multilayer metal foil may be made of a low-cost material that must have good conductivity, preferably Copper or tin.
• the last layer of the multilayer metal foil on the side remote from the semiconductor component is a silver layer and / or tin layer and / or zinc layer and / or copper layer for further connection.
• structuring of the metal foil takes place simultaneously during the contacting process.
• Structuring means that a separation between the areas in which an electrical contact was generated by means of the metal, and the areas in which the metal foil was not melted, arises.
• the advantage here is that thereby the metal foil in the areas where no contact has taken place, can be removed easily and without additional separation step from the semiconductor surface.
• predetermined breaking points are introduced into the metal foil in an additional method step B-a before method step C. This has the advantage that, in particular when using thicker and in particular multilayer metal foils, a defined parting line is predetermined. In this way, in particular, the risk that film is torn off when removing the film, even in a molten area, is considerably reduced.
• the metal foil is at least partially spaced apart from the semi-ferritic component in the non-fused areas before the structuring step so that no contact is made with the semiconductor component at the heated portions. In this way, in particular, it is avoided that the metal foil adheres to the semiconductor device in the non-fused areas during the separation step.
• a safe and inexpensive spacing is achieved in a preferred embodiment of the method according to the invention by the metal foil is at least partially spaced from the Haibleiterbauelement by heating the semiconductor device and / or by suction from above, and / or by blowing from below.
• a laser particularly preferably a pulsed laser, is used in the generation of predetermined breaking parts in the structuring step.
• the use of a laser for processing solar cells is known per se, so that it is possible to resort to existing devices and in particular deflection units for the laser beam. It is especially made
• LFC laser fired contacts
• a laser with a wavelength range from 1 90 nm to 1 1 ⁇ used preferably in the range of 1030 nm to 1064 nm.
• a laser with pulse lengths of one ns to several ps used more preferably in the range of 1 s to 1 00 ⁇ . It is also within the scope of the invention to perform the structuring step with a laser in continuous wave mode (cw) or a cw laser in modulated operation.
• the metal foil is fastened to the semiconductor component at least during method step B.
• the metal foil preferably rests flat against the semiconductor component during melting, since, for example, air entrapment between the foil and the semiconductor component in the region to be fused may result in inaccuracies in the production of the metal structure. This may be due to the fact that the metal foil is completely or partially vaporized due to the lack of thermal contact with the semiconductor device in the local heating and thus forms no or only an insufficient, a high contact resistance having metal structure.
• the metal foil is therefore stretched during the process step B on the semiconductor device, and / or sucked on this and / or blown on this.
• the suction and / or blowing of the metal foil offers a process-technically simple and in particular non-contact possibility of ensuring the contact between metal foil and semiconductor component in method step B.
• the heating of the metal foil takes place by illumination of the side of the semiconductor component facing away from the metal foil. This preferred embodiment of the method according to the invention makes it possible to melt the metal foil locally at the boundary layer metal foil semiconductor component.
• a laser is preferably used for the melting of the metal foil which is not or only slightly absorbed by the semiconductor component, in particular by a silicon layer, so that the local heating takes place essentially at the local metal foil semiconductor component at the boundary layer.
• the use of a laser having a wavelength in the range of 1200 nm to 1 pm is advantageous, in particular a C0 2 laser.
• multilayer metal foils In the case of illumination from the side facing away from the metal foil, use of multilayer metal foils in particular is preferred. In this case, it is advantageous in particular that further possible metal layers are not or only slightly melted on the side of the metal foil facing away from the semiconductor component. This ensures that only the semiconductor component facing layer of the multilayer metal foil is melted to form the electrical contact with the semiconductor device, whereas the other layers of the multilayer metal foil remain unchanged in structure and thus may be formed in particular for a low line resistance. As a result, multilayer metal contacts with different functionalities can be produced in one method step.
• a multilayer film which comprises a copper layer which does not directly adjoin the semiconductor component, ie is a middle layer or the layer facing away from the semiconductor component.
• a copper layer when using a copper layer, the problem was that the copper layer was also melted and therefore copper atoms embedded in the semiconductor device and adversely affected the electrical properties, especially when using a silicon semiconductor device.
• a laser is used for melting the metal foil whose beam profile has a higher intensity at the edges than in the middle.
• intensity at the edges rather than at the center means that the intensity of the beam profile perpendicular to the direction of movement of the laser relative to the surface of the semiconductor device has a lower intensity in a middle region than in the two outer regions
• the metal foil Due to the high laser intensity at the edges of the beam profile, the metal foil is contacted here with the Halbieiterbauelement and simultaneously generates a predetermined breaking point, in the middle region with low laser intensity, the metal foil remains largely preserved and thus ensures sufficient conductivity.
• the advantage here is that thereby the metal foil in the areas where no contact has taken place, can be removed easily and without additional separation step from the surface of the semiconductor device.
• the method according to the invention is designed as an at least two-stage metallization process: First, as described above, a metal structure is formed by means of the metal foil. This serves as a seed layer, which is reinforced metallically in a second step of the metallization process.
• metal preferably galvanically, is deposited on the metallic contacts which were produced as a seed layer in the first step, ie the contacts are preferably galvanically reinforced.
• the galvanic amplifiers kung can be used on known processes. In particular, it is advantageous to carry out the reinforcement with a different and preferably less expensive metal to the seed layer.
• a thin metal foil is preferably used to produce the seed layer, so that the contacting step and the structuring step take place simultaneously. This results in a low process complexity. Furthermore, a costly metal, for example silver, is typically used as seed, so that the use of a thin metal foil reduces costs.
• the metal foil used in the production of the seed layer has a total thickness of less than 3 pm, preferably less than 2 ⁇ .
• a laser with pulse lengths in the range of 10 ns to 100 ns is used for the production of seed layers, in particular when using a metal foil having a total thickness of less than 3 ⁇ m, preferably less than 2 m.
• a seed layer of silver, titanium or nickel and, for contacting p-doped regions, a seed layer of aluminum, titanium or nickel is preferably formed by means of the metal foil.
• n-doped regions of the semiconductor device are metallized in a first implementation of the method.
• a thin metal foil is used in the first implementation of the method, so that the contacting step and the structuring step occur simultaneously.
• p-doped regions of the semiconductor component are metallized.
• a structuring step is carried out to produce predetermined breaking points.
• this preferred embodiment is thus possible in a simple and cost-effective manner to contact p- and n-doped regions.
• a cost effective method results if p- and n-doped regions are contacted with the same metal foil.
• different metal foils are used for the contacting of the n-doped regions on the one hand and the p-doped regions on the other hand, so that in particular the metal used in each case can be selected with regard to a low contact resistance.
• it is advantageous in this case to heat the last applied metal foil in such a way that heating takes place on the underside.
• the above-described object is furthermore achieved by a machining table according to claim 14.
• the machining table according to the invention serves to carry out the above-described method according to the invention or preferably a preferred embodiment of the method according to the invention.
• the processing table according to the invention comprises a support region for a semiconductor component, a fixing region for the semiconductor component, a fixing region for the metal foil and at least one blow-off opening. It is essential that the blow-off opening is arranged between the fixing region for the metal foil and the support region for the semiconductor component. For this purpose, the blow-off opening is preferably connected to a blow-off channel.
• the support area is preferably arranged centrally.
• the semiconductor device is fixed in the Aufiage Scheme when using the work table according to the invention.
• the fixed semiconductor device is covered with a metal foil.
• the fixing region for the metal foil is arranged surrounding the central supporting region for the semi-ferritic component and configured in such a way that the metal foil is fixed on the semi-ferritic component without air inclusions. Any air pockets lead in carrying out the method according to the invention that the Metailfoiie is completely or partially evaporated due to the lack of thermal contact with the semiconductor device in the local heating and thus no or only insufficient, a high contact resistance having metal structure is formed.
• a gas preferably air
• the blow-off opening is arranged between the fixing region for the metal foil and the mounting region for the semiconductor component.
• predetermined breaking points after spacing the film by supplying gas through the blow-off opening. This avoids that in the production of predetermined breaking points at the predetermined breaking points Metailfoiie adhered to the Halbieiterbauelement. Furthermore, a thermal contact at the predetermined breaking points between Metailfoiie and Halbieiterbauelement is avoided, so that in a simple manner by means of local heat, preferably by a laser, the metal foil thinned at the Solibruchstellen or can be evaporated.
• the fixing region for the Halbieiterbauelement is designed as at least one suction port, which is connected to a first suction line. Via the first suction line and the suction The semiconductor component can be subjected to a vacuum / negative pressure and thus fixed to the support region.
• the fixing region for the metal foil is designed as an intake channel enclosing the bearing area for the semiconductor component.
• the suction channel is connected to a second suction line. Via the second suction line and the suction channel, the IVIetallfolie can be applied with vacuum / negative pressure and thus fixed on the semiconductor device.
• the support area is formed as a depression, such that when the semiconductor component is inserted in the recess, the semiconductor component and the surface of the processing table adjoining the recess form a planar surface.
• the inventive method is particularly suitable for the formation of metallic contacting structures on one side contacted solar cells and in particular of back-side contact solar cells.
• Figure 1 a to Figure 1 e process steps A to D of a first embodiment of the method according to the invention
• Figure 2a to Figure 2d process steps a to d of a second embodiment of the method according to the invention
• FIG. 5 shows a schematic representation of the processing table according to the invention.
• FIG. 6 shows a plan view of the schematic illustration of the rear side of a rear-side contact solar cell in the figures, and the same reference symbols designate identical or equivalent elements.
• FIGS 1 to 4 are schematic views of a semiconductor device which is a photovoltaic solar cell or a precursor of such a solar cell during the manufacturing process.
• a partial section is shown schematically; the solar cell is continued analogously on both sides.
• Like reference numerals in the figures indicate the same or equivalent elements.
• FIG. 1a shows a semiconductor component 1 comprising a semiconductor layer 2 with a p-doped region 2a and an n-doped region 2b.
• the n-doped region 2 b is coated with an insulating layer 3.
• the insulating layer is on the one hand designed to be electrically insulating and moreover has a passivation effect with respect to the surface of the semiconductor layer 2 adjoining the insulating layer 3, so that the charge carrier recombination velocity and thus recombination losses are reduced at this surface.
• the metal foil 4 is applied to the insulating layer 3.
• FIG. 1 a thus shows the state after carrying out method step A.
• the second layer of multilayer Metal foil on the side facing away from the Halbieiterbauelement is a silver layer for further interconnection.
• FIG. 1 b shows a schematic representation of method step B of the method.
• the metal foil 4 is locally heated by means of laser beams 5.
• the laser beams are generated by a laser, not shown, and sequentially directed to the areas 5a, 5b to be heated by means of an optical deflection unit (not shown).
• the laser used is a pulsed Nd: YAG laser with a wavelength of 1 064 ⁇ , and a pulse duration of 100 ns.
• the method produces line-like metallic contacting structures.
• the laser beams are therefore moved approximately along a line which is perpendicular to the plane of the drawing in FIG. 1 (and also in the methods described below for FIGS. 2, 3 and 4).
• the metal foil 4 is lifted off the semiconductor layer 2 at the non-contacted regions before the structuring step. This can be done by, for example, heating the semiconductor device 1. As a result, the metal foil 4 expands and bulges away from the semiconductor layer 2 between the generated contacts 6. Alternatively, the metal foil may also be spaced from the semiconductor device 1 by suction from above or blowing from below. By lifting off the metal foil 4, one or more air gaps 23 are formed between the metal foil 4 and the semiconductor layer 2.
• FIG. 1 d shows the structuring step of the metal foil 4 by means of laser radiation 5.
• 6 solid-state breaking points are engraved in the metal foil 4 which is spaced apart from the semiconductor surface.
• the predetermined breaking points can be designed as a perforation and / or removal of metal foil for local thickness reduction.
• the metal foil is affixed to the non-fused regions, i. H. outside the contacts 6, removed. This is done by peeling off the film.
• FIG. 1 e shows, in a last method step, the remaining previously produced contacts 6 after removal of the metal foil 4.
• Figures 2a to 2d show the schematic representation of process steps of a second embodiment of the method according to the invention.
• FIG. 2 a shows a semiconductor component 1 equivalent to FIG. 1 a. To avoid repetition, only the differences between the individual exemplary embodiments of the method according to the invention will be discussed below.
• a thin metal foil 7, with a thickness of about 2 ⁇ m, is applied.
• FIG. 2b shows the local heating by means of laser radiation 5 in method step B.
• a melt mixture of the metal foil 7 and the insulating layer 3 is formed at the heated point.
• the metal is melted by the insulating layer 3.
• the semiconductor layer 2 is not melted with.
• the melt mixture has solidified, there is an electrical contact 6 to the underlying semiconductor component 1.
• the thin metal foil 7 is used, the contacted area is simultaneously separated from the foil, because upon solidification, the liquid metal contracts due to the surface tension and releases it. There is a separation between the areas where the metal has been melted and the areas where the metal has not been melted.
• FIG. 2 d shows the metal-reinforced contacts 9 in an additional method step.
• metal for example, is electrodeposited on the metallic contacts 8, which were produced as a seed layer in the first step.
• galvanic reinforcement of the seed layer serving as contacts 8 can be made to known methods.
• FIGS. 3a to 3c A further exemplary embodiment of the method according to the invention is shown schematically in FIGS. 3a to 3c.
• FIG. 3 a shows a semiconductor component 1 equivalent to FIGS. 1 a and 2 a.
• the Metallfoüe 4 may optionally be different thickness, made of different materials or multi-layered. In this case, it is possible, for example, to coat the lower side of the film in such a way that the contact formation is improved and the upper side of the film is optimized with regard to a simpler connection.
• the central layer of the multilayer metal foil 4 may consist of a low-cost material, which only has to have a good conductivity.
• a multilayer metal foil of three layers having the following structure is used.
• the layer facing the semiconductor device 1 is made of titanium and has a thickness of about 200 nm. This is followed by an aluminum layer with a thickness of approximately 10 ⁇ m as the middle layer.
• the subsequent layer facing away from the semiconductor component 1 is made of aluminum and has a thickness of 200 nm.
• FIG. 3b shows the method step B in that the metal foil 4 is locally heated by means of laser radiation 5.
• a laser is used with a beam profile having a higher intensity at the edges than at the center.
• the beam profile has along the dashed line 1 following intensity curve: follows in the order given a minimum of intensity at an intensity minimum and then a second intensity maximum.
• the intensity of the beam profile therefore has a lower intensity perpendicular to the direction of movement of the laser relative to the surface of the semiconductor component 1 in a middle region than in the two outer regions. This is shown qualitatively (with arbitrary units) in sub-picture 3b.1, where the Y-axis shows the intensity and the X-axis the spatial position along the line 1 1.
• a suitable beam profile results, for example, from the superimposition of two laser beams with Gaussian intensity distribution, such that the two intensity maxima have the desired distance from one another.
• the local heating produces a melt mixture of " melted metal foil 4 and insulating layer 3.
• the liquid metal contracts due to the surface tension and creates a separation between the areas where the metal has been melted and the areas where the metal is not was melted.
• Figure 3c shows the remaining previously created contacts 6 after peeling off the film.
• FIGS. 4a to 4h schematically show the method steps of a further embodiment of the method according to the invention.
• FIG. 4a shows a semiconductor device 1, which is formed as a precursor of a back-side contact solar cell.
• the semiconductor device 1 comprises a semiconductor layer 13 with a comb-like doping structure 14 and an insulating layer 3.
• the comb-like doping structure is common in rear-side contact solar cells and shown as a plan view of the back of the semiconductor device 1 in Figure 6:
• the base doping of the semiconductor device is back with a comb-like emitter doping as a doping structure 14, so that in the illustration according to FIG. 6 in the direction A there are alternatingly p-doped regions 2a and n-doped regions 2b.
• FIG. 4b shows the semi-conductor component 1 from FIG. 4h, which is additionally coated with a metal foil 4.
• different thicknesses of different materials preferably titanium, nickel or silver can be used.
• FIG. 4c shows the local heating of the metal foil 4 by means of laser radiation 5. At the irradiated parts of the metal foil 4 and the insulating layer 3 are melted. This creates a contact 6 to the underlying semiconductor device. 1 The locations for the local heating are selected such that a p-doped 2a and an n-doped 2b region of the doping structure 14 are alternately contacted.
• FIG. 4d shows the remaining metallic contacts 6 which have been produced after the metal foil 4 has been removed.
• the adjoining p- and n-doped regions of the doping structure 14 are now each separately electrically contacted.
• FIG. 4e shows the second iteration of the contacting method.
• a second thicker metal foil 15 made of a cost-effective material, such. As aluminum, placed on the contact structure 6 previously generated.
• FIG. 4f shows the local heating of the second metal foil 15 by means of laser radiation 5.
• the metafoil 15 melts at the irradiated points and forms an alloy with the contacts 6 present on the underside of the second metal foil 5.
• suitable focusing optics an irradiation spot up to ⁇ ⁇ thin can be realized here.
• FIG. 4g shows the structuring step for the second metal foil 15. At the edges of the contacts 5 predetermined breaking points are engraved by means of laser radiation. An air gap 23 between the second metal foil 1 5 and the semiconductor component 1 is located through the first contact structure 6, since the contact structure 6 prevents the metal foil 1 5 from being applied to the semiconductor component 1. The second metal foil 1 5 can thus be severed by means of laser radiation 5, without producing further contacts on the semiconductor device 1.
• FIG. 4h shows a generated two-layer contact structure for a rear-side contact solar cell after the second metal foil 15 has been removed.
• the alternating metallic contact 6 corresponds to the doping structure 14 of the rear-side contact solar cell.
• the direct contact between the semiconductor layer 2 and contact structure 6 is formed with a metallization with low contact resistance and high conductivity.
• the second part of the contact structure 6 may be formed of a less expensive material.
• Figure 5a shows a schematic representation of an embodiment of a processing table according to the invention.
• the processing table 1 7 comprises a central support region 1 8 for a semiconductor component 1, a fixing region 1 9 for the semiconductor component, a fixing region 20 for the metal foil 4 and a blow-off opening 21.
• the fixing areas 1 9 and 20 are in the present embodiment suction openings, which are connected to suction lines 24.
• the blow-off opening 21 is connected to a blow-off channel 22 and arranged between the fixing region for the metal foil 20 and bearing area 1 8.
• the arrangement of the blow-off opening 21 between the fixing region for the metal foil 20 and the support region for the semiconductor component 1 8 after the local melting through the blow-off opening 21 can supply a gas, preferably air, so that the metal foil 4 is blown with the gas and thus at least partially spaced in the non-melted areas of the Haibleiterbauelement 1.
• a gas preferably air
• the metallic contact structures between the metal foil and the semiconductor component do not extend over the entire width of the semiconductor component. They do not form airtight barriers, so that the metal foil is lifted off the surface of the semiconductor device even in the central regions (eg, between two metallic contact structures).
• the processing table according to the invention finds in particular an advantageous application when in the method according to the invention after the melting of the metal foil in a further process step predetermined breaking points are generated in the metal foil, such as the associated embodiment of the inventive method, shown in Figures 1 c to 1 d described ,
• the support region 18 is formed as a depression, such that when inserted into the recess semiconductor device 1, the semiconductor device 1 with the laterally adjacent surface of the processing table 17 forms a flat surface.

Landscapes

• Electrodes Of Semiconductors (AREA)
• Photovoltaic Devices (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=48918400

Family Applications (1)

Country Status (4)

Cited By (8)

Families Citing this family (1)

Citations (4)

Family Cites Families (4)

• 2012
  • 2012-08-10 DE DE102012214254.1A patent/DE102012214254A1/de not_active Withdrawn
• 2013
  • 2013-08-02 CN CN201380052669.9A patent/CN104737300A/zh active Pending
  • 2013-08-02 EP EP13745646.3A patent/EP2883247A1/fr not_active Withdrawn
  • 2013-08-02 WO PCT/EP2013/066328 patent/WO2014023668A1/fr not_active Ceased

Patent Citations (4)

Non-Patent Citations (5)

Also Published As

Similar Documents

Legal Events