HK1181464A - Optical receiver architecture using a mirrored substrate - Google Patents

Description

Optical receiver architecture using mirrored substrates

Background

1. Field of the invention

Embodiments of the invention generally relate to structures for guiding optical signals in photonic devices. More particularly, certain embodiments relate to a reflector die for reflecting an optical signal into a photodetector to produce a corresponding electrical signal.

2. Background of the invention

Architectures for photonic devices typically rely on silicon-layer waveguide-based approaches, where a planar silicon layer of a substrate serves as a waveguide for the transmission of optical signals. Due to the absorptive nature of silicon, such an approach can only be implemented for a limited range of optical signal wavelengths. For example, silicon layer waveguide structures are compatible with larger wavelength optical signals (e.g., lasers with wavelengths near 1310 nm). However, due to the absorption coefficient of silicon at such wavelengths, optical signals of smaller wavelengths (e.g., in the range of 850 nm) cannot be efficiently exchanged.

In these photonic architectures, such wavelength ranges may also limit the use of photodetectors for converting optical signals into corresponding electrical signals. For example, photodetectors such as Normal Incidence Photodetectors (NIPDs) can be used quite easily for lasers operating in the 850nm range. However, for larger wavelength (e.g., 1310 nm) lasers, the active area of the NIPD must be much smaller to achieve high bandwidth performance at such larger wavelengths. For such larger wavelength signals, the accuracy required to align the optics (e.g., lenses, mirrors, etc.) with such small active areas of the photodetectors is very difficult to achieve on a volumetric basis.

Drawings

Various embodiments of the present invention are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which:

fig. 1A through 1C are block diagrams illustrating select elements of a reflector die for providing a reflective target area for an optical signal according to an embodiment.

Fig. 2 is a block diagram illustrating select elements of a substrate etched and cut to provide a reflector die according to an embodiment.

Fig. 3A and 3B are block diagrams illustrating selected elements of a method for metalizing a reflector die according to an embodiment.

Fig. 3C and 3D are block diagrams illustrating selected elements of a method for bonding reflector dies to create a die assembly according to an embodiment.

Fig. 3E and 3F are block diagrams illustrating selected elements of a method for packaging a die assembly according to an embodiment.

FIG. 4 is a block diagram illustrating select elements of a system for directing and processing optical signals according to an embodiment.

Detailed Description

Certain embodiments provide a reflector die that allows operation of optical receivers that are compatible with 1310nm and 850nm optical signals, the 850nm optical signals being necessary for backward compatibility with existing optical communication standards. Unlike waveguide-based silicon photonics, various embodiments implement an architecture in which free-space optics can focus both wavelengths onto a Normal Incidence Photodetector (NIPD). In such an architecture, optical signals may enter a die assembly, which is connected to a substrate (e.g., a circuit board), along a side surface that is perpendicular to the substrate.

Various embodiments include a reflector die made of a substrate that is metallized to include facets for optical quality of reflected light. The reflector die may also include optical alignment features (such as V-grooves) for providing precise alignment when bonding the reflector die to one or more other components. Some embodiments further include a Normal Incidence Photodetector (NIPD) and/or an associated Integrated Circuit (IC), such as a transimpedance amplifier (TIA) bonded to the reflector die. The reflector die may provide a bond pad or similar bonding structure to which the NIPD and/or TIA may be bonded. Additionally or alternatively, the reflector die may include one or more traces for interconnecting a plurality of components bonded to the reflector die.

Fig. 1A is a block diagram illustrating selected elements of a reflector die 105 according to an embodiment from a first view 100a, the reflector die 105 being used to provide a target area for guiding a light signal. The reflector die 105 may be made of or include a high impedance silicon substrate, where the low doping of the substrate mitigates capacitive effects in high frequency signal communication. The first view 100a shows a coupling surface 110 of a reflector die 105, the coupling surface 110 being used to couple the reflector die 105 to one or more other dies-e.g., to form a die assembly. In an embodiment, such a die assembly may be packaged in an apparatus for processing optical signals received from, for example, a fiber optic cable, waveguide, or other similar signal communication medium.

One or more sides or edges of the coupling surface 110 may be defined by one or more other surfaces (referred to herein as side surfaces) of the reflector die 105 that abut the coupling surface 110, respectively. For example, one or more such side surfaces may be considered "vertical" surfaces relative to a more "horizontal" coupling surface 110. By way of illustration and not limitation, a side surface 120 (shown laterally in view 100 a) of reflector die 105 may at least partially abut coupling surface 110 to define a side thereof. Alternatively or additionally, the side surface 120 may at least partially define a side of the coupling surface 110 by providing a surface against which a slope is formed with the coupling surface 110. By way of illustration and not limitation, the bevel surface BvS130 of reflector die 105 is formed by a bevel relative to coupling surface 110 and side surface 120. The other side surfaces shown in view 100a are merely to illustrate some of the termination range of reflector die 105.

In an embodiment, BvS130 may provide a target area for an optical signal to be reflected by reflector die 105. A reflective coating (indicated by the shaded area in view 100 a) may be deposited on the BvS130 to reflect light (e.g., laser signal) incident on its target area. In an embodiment, the reflective coating provides an optical quality mirror surface treatment to at least a portion of the BvS 130. It is understood that additional, smaller, and/or alternative reflective surfaces may be deposited on reflector die 105 in various embodiments.

Reflector die 105 may further include one or more grooves in coupling surface 110, each of the one or more grooves providing a respective leverage point for aligning the optical signal target area of BvS 130. In embodiments, the one or more alignment grooves may extend differently along the coupling surface 110 and through side surfaces (such as surface 120) that define sides of the coupling surface 110. Alternatively or additionally, the one or more alignment grooves may extend differently through a beveled surface such as BvS 130. In the illustrated case of the first view 100a, the coupling surface 110 is shown to include two grooves 140, with each groove 140 extending through the side surface 120 on either side of the slope forming the BvS 130.

It should be understood that reflector die 105 may include any of a variety of additional or alternative configurations of a bevel surface formed by a bevel relative to a coupling surface and a side surface and one or more grooves in the coupling surface for aligning a target region in the bevel surface, in accordance with various embodiments.

Fig. 1B is a block diagram illustrating select elements of reflector die 105 from a second view 100B. View 100b shows side surface 120 in a forward direction, while coupling surface 110 is shown sideways. In an embodiment, BvS130 can provide, in combination with the reflective coating of BvS130, a target region that reflects optical signals incident on reflector die 105 and passing through the plane defined by side surface 120. In an embodiment, BvS130 is formed at a bevel angle of 54.7 degrees or less relative to coupling surface 110, e.g., a forty-five degree (45) angle. For example, a 54.7 degree angle in the crystal plane may form naturally after anisotropic etching. If the etchant is selected to have a lower selectivity to the crystal plane, the angle may be less than 54.7 degrees.

View 100b also shows the various intersections of the grooves 140 with the side surfaces 120. A particular groove 140 may be characterized, for example, in terms of a width along a side defined by the coupling surface 110 and another surface (e.g., the side surface 120) through which the groove 140 extends. Alternatively or additionally, the groove 140 may be characterized by a depth below the coupling surface 110 and/or an extension along the coupling surface 110 and away from intersecting surfaces (e.g., the side surface 120). By way of illustration and not limitation, the width and depth of trench 140 may be 500 μm and 350 μm, respectively. However, it should be understood that the dimensions of each of the one or more grooves 140 may be different in different embodiments. For example, certain dimensions of one or more grooves 140 may be selected based on the particular alignment tool used in aligning the target region of the BvS 130.

In an embodiment, BvS130 can be characterized in terms of the width of BvS130 along the direction defined by the intersecting planes defined by coupling surface 110 and side surface 120, respectively. Alternatively or additionally, BvS130 may be characterized in terms of an extension in coupling surface 110 and away from side surface 120 and/or an extension in side surface 120 and away from coupling surface 110.

In an embodiment, the size, shape, and/or orientation of BvS130 may be selected based on the size of the one or more photodetectors used to receive the laser light (which has been reflected by reflector die 105). For example, one or more dimensions of BvS130 can be selected to present a particular target distribution to a set of photodetector elements in a photodetector die (not shown) coupled to coupling surface 110. In an embodiment, the BvS130 can have a target profile sufficient to present a length spanning 1000-.

Fig. 1C is a block diagram illustrating select elements of reflector die 105 from a third view 100C. In view 100c, both the coupling surface 110 and the side surface 120 are shown laterally. View 100c also shows the respective extension lengths of each of BvS130 and trench 140 along coupling surface 110 and away from surface 120. It should be understood that in various embodiments, the structure of the reflector die 105 shown may differ-for example, in the following respects: the shape and scale of grooves 140, the shape and scale of BvS130, and/or the relative configuration of BvS130 and grooves 140 with respect to each other.

Fig. 2 is a diagram 200 illustrating select elements of a reflector die substrate 205 according to an embodiment. The structures on the reflector die substrate 205 may be formed on a substrate wafer and then cut from the wafer to form the reflector die. In an embodiment, the resulting die includes some or all of the features of reflector die 105. For example, in an embodiment, an area of the coupling surface 210 of the reflector die substrate 205 may correspond to the coupling surface 110. A plurality of side surfaces (e.g., side surface 215) of reflector die substrate 205 illustrate side surfaces that may be formed in the resulting reflector die. However, it should be understood that such side surfaces need not be formed when fabricating other structures (e.g., a plurality of trenches) shown in view 200.

The reflector die substrate 205 may include a bevel trench 230 and one or more alignment trenches 240 formed in the coupling surface 210. At some point during manufacturing, dicing portions of the reflector die from the reflector die substrate 205 may include performing side surface die dicing 225. For example, the side surface die cut 225 may cut (e.g., bisect) along the length of the bevel trench 230 such that a portion of the bevel trench 230 remaining as part of the resulting die forms a bevel between the coupling surface 210 and the side surface (the bevel being the result of the side surface die cut 225). In embodiments, the resulting bevel may include some or all of the features of BvS 130.

In an embodiment, some or all of the bevel groove 230 and the one or more alignment grooves 240 may be formed in the coupling surface 210 before the final reflector die is cut from the reflector die substrate 205. Such trenches in the coupling surface 210 may be formed using a crystallographic etching process, such as potassium hydroxide (KOH) etching, tetramethylammonium hydroxide (TMAH) etching, ethylenediamine pyrocatechol (EDP) etching, ammonium hydroxide (NH)₄OH) etch or other such etch process. The etching process may form some or all of the trench structures shown in the reflector die substrate 205-e.g., using a patterned silicon nitride or thermal oxide mask.

After forming the one or more grooves 240 and the bevel groove 230, the area of the coupling surface 110 may be metallized, for example, including depositing a reflective coating on the surface of the bevel groove 230. For example, the area of the bevel groove 230 used to form the bevel surface of the final resulting reflector die may be coated with gold (Au) to provide reflectivity of the target area thereon. Such metallization may be performed using sputtering, evaporation, or other such techniques for depositing gold or other reflective metal coatings to give the bevel surface an optical quality mirror surface treatment.

After forming the bevel trench 230 and the one or more alignment trenches 240 in the reflector die substrate 205, and after metallizing at least the reflective portions of the bevel trench 230, the reflector die including these trenches can be cut from the reflector die substrate 205, including performing a side surface die cut 225. It is understood that cutting the reflector die from the reflector die substrate 205 may be performed after fabricating additional structures for the reflector die (not shown) on the reflector die substrate 205. For example, the side surface die cut 225 and/or any other such cuts may be performed after signal traces and/or bonding structures (e.g., bond pads and/or stud bumps) have been deposited on the coupling surface 210 in various ways. Additionally or alternatively, one or more other dies may be bonded to the coupling surface 210 before the reflector die is cut from the reflector die substrate 205 — i.e., the cut die is already coupled to the one or more other dies. In an embodiment, the reflector die is cut from the reflector die substrate 205 before the reflector die is bonded to the package substrate in any manner.

For the purpose of illustrating features according to certain alternative embodiments, view 200 shows an alternative location 235 for a bevel groove and an alternative location 245 for an alignment groove. Alternate location 235 illustrates an embodiment in which alignment trench 240 will extend through a bevel made from alternate bevel trench 235 in the final resulting die cut from reflector die substrate 205. Additionally or alternatively, alternate location 245 illustrates an embodiment in which an alternate alignment trench 245 would extend through side 215 in the final resulting die cut from reflector die substrate 205, side 215 not being the side of the bevel formed by bevel trench 230. It should be understood that various other configurations of the alignment groove 240 and the bevel groove 230 relative to each other may be implemented in accordance with various embodiments.

Fig. 3A is a first view 300a illustrating selected elements of a method for manufacturing a device for guiding an optical signal according to an embodiment. The fabrication may include operations for creating multiple structures of reflector die 305. For example, reflector die 305 may include some or all of the features of reflector die 105. In an embodiment, the reflector die 305 may represent the final resulting reflector die cut from the reflector die substrate 205.

In an embodiment, the fabrication of the structure for reflector die 305 may include etching one or more alignment trenches 340 in the coupling surface 310 for reflector die 305 and forming a bevel surface BvS330 by creating a bevel between the coupling surface 310 and the side surface 320 of reflector die 305. For example, creation of the BvS330 may be according to the techniques described with respect to the bevel groove 230. Fabrication of the structure for reflector die 305 may further include depositing a reflective coating on BvS 330. Although shown as individual reflector dies 305, it should be understood that many of the manufacturing operations shown in fig. 3A-3F may be performed before the reflector dies 305 have been cut from the substrate wafer.

Metallization processes may additionally or alternatively be performed to provide one or more traces 355 and/or one or more bonding structures 350, such as bond pads and/or stud bumps, on the coupling surface 310. The particular number, size, shape, configuration, etc. of such traces 355 and/or bonding structures 350 may depend on the one or more dies to be bonded with the coupling surface 310. In an embodiment, a metal such as gold or nickel/gold may be deposited to form such traces 355 and/or bonding structures 350 — for example, using a deposition process that is compatible with the layout present on the substrate wafer of reflector die 305. For example, if standard thick resist spin coating is not possible, photolithography can be performed using spray coating or electrodeposition of resist.

Fig. 3B is a second view 300B illustrating selected elements of the manufacturing method illustrated in fig. 3A. View 300b shows side surface 320 in a forward direction, while coupling surface 310 is shown laterally. It should be understood that in embodiments, the side surface 320 may be formed only after etching and/or depositing additional or alternative structures in the substrate wafer from which the reflector die 305 is later cut.

Fig. 3C is a third view 300C illustrating selected elements of the manufacturing method illustrated in fig. 3A and 3B. View 300c shows an exemplary embodiment in which a die assembly is created by bonding one or more integrated circuit dies to a coupling surface 310.

For example, the photodetector die 360 may be bonded to one or more bonding structures 350 disposed on the coupling surface 310. For example, the photodetector may be a germanium photodiode or other type of photodetector. The photodetector die 360 may include one or more photodetector elements for receiving optical signals for conversion into corresponding electrical signals. In an embodiment, the photodetector die 360 may include one or more normal incidence amplifiers. Bonding the photodetector die 360 to the coupling surface 360 may include: the active area (e.g., detection area) of the photodetector die 360 is positioned to overlap and face the area of the BvS330 where the reflective coating is disposed. For example, the overlap of BvS330 with the active area of photodetector die 360 may be, for example, along a direction perpendicular to side surface 320. Such positioning of the photodetector die 360 relative to the reflective coating of the BvS330 can allow optical signals incident on the target region of the BvS330 to be reflected onto the active region of the photodetector die 360.

Additionally or alternatively, the amplifier die 370 may be bonded to one or more other bonding structures 350 disposed on the coupling surface 310. In an embodiment, one or more bonding structures 350 bonded to the photodetector die 360 and one or more other bonding structures 350 bonded to the amplifier die 370 may be coupled in a variety of ways by corresponding ones of the traces 355 disposed on the coupling interface. Such traces 355 may allow the photodetector die 360 to provide an electrical signal generated by detecting and converting the optical signal reflected from the BvS330 to the amplifier 370. The amplifier die 370 may amplify the signals received from the photodetector die 360 via the traces 355 before providing the amplified signals to other circuit components (not shown). In an embodiment, the amplifier die 370 includes a transimpedance amplifier (TIA).

The photodetector die 360 and the amplifier die 370 may each include respective bonding structures (e.g., bonding pads and/or stud bumps, not shown) for bonding to respective ones of the bonding structures on the coupling surface 310. In one embodiment, for example, photodetector die 360 and/or amplifier die 370 may have aluminum, gold, or similar pads with gold stud bumps. Either or both of the dies may then be bonded to respective ones of the bonding structures 350. For example, such bonding may be performed using thermo-compression or thermo-ultrasonic bonding.

Fig. 3D is a fourth view 300D illustrating selected elements of the manufacturing method illustrated in fig. 3A to 3C. View 300d shows side surface 320 in a forward direction, while coupling surface 310 is shown laterally. In an embodiment, the bonding of the photodetector die 360 and/or the amplifier die 370 to the coupling surface 310 may be performed after the reflector die 305 has been cut from the substrate wafer. Cutting the reflector die 305 from the substrate wafer may create one or more of the side surfaces (e.g., including the side surface 320) in a variety of ways, with the alignment trench 340 passing through a corresponding one of the one or more side surfaces in a variety of ways.

The extension of the alignment trenches through the side surfaces and/or BvS130 (e.g., one or more trenches 340 through side surface 320) may provide access to the alignment trenches 340. Thus, the one or more alignment grooves 340 can provide respective leverage points for aligning the pins to give precise alignment of the die relative to the target area of the BvS330 to facilitate coupling the die to the coupling surface 310. In an embodiment, some or all of the alignment grooves 340 may receive corresponding alignment pins to apply leverage for precise manipulation, positioning, and/or securing of the photodetector die 360 and/or the amplifier die 370 for bonding to the coupling surface 310.

Fig. 3E is a fifth view 300E illustrating selected elements of the manufacturing method illustrated in fig. 3A to 3D. View 300e illustrates features of the operation of the die assembly shown in package view 300 c. In an embodiment, the die assembly including the reflector die 305, the photodetector die 360, and the amplifier die 370 may be bonded to the package substrate 380, for example, by one or more bonding structures 350 disposed on the coupling surface 310. The package substrate 380 may be a laminate material such as FR-4 or other such material used for integrated circuit packaging. Package substrate 380 is illustrative of one type of package substrate, and it should be understood that any of a variety of additional or alternative package structures may be bonded to the die assembly. For example, bonding of the package substrate 380 may be accomplished using a standard soldering process. In one embodiment, the Ni/Au deposition of the bonding structure 350 will be as a metallurgy under the bump pad that is compatible with standard lead-free soldering for forming this connection, with nickel as a barrier layer and gold as a fluxing material.

Fig. 3F is a sixth view 300F illustrating selected elements of the manufacturing method illustrated in fig. 3A to 3E. The combination of the die assembly and the package substrate 380 may be provided as or incorporated into a device for receiving an optical signal for conversion to an electrical signal. Such devices may include, for example, optical Universal Serial Bus (USB) devices.

Fig. 4 is a high-level diagram of selected elements of a system 400 according to an embodiment, the system 400 being used to direct and process optical signals. The system 400 may include optical signal reflecting and converting structures such as those produced by the operations of fig. 3A through 3F. In an illustrative embodiment, system 400 may include a die assembly including reflector die 405, photodetector die PD460, and package substrate 480. The system 400 may further include an amplifier (not shown) for amplifying the electrical signal generated by the PD460 by converting the optical signal.

For example, the system 400 may include an optical medium 410 (e.g., a fiber optic cable or waveguide) for directing a laser signal 425 to the bevel surface BvS430 of the reflector die 405. The circuit board 490 may include or be coupled to positioning hardware 415 to position and/or orient the optical media 410 to direct the laser light 425 toward the target area of the BvS 430. In an embodiment, the BvS430 may comprise a reflective coating on the target region for reflecting the laser signal 425 onto the active region of the PD 460. It should be understood that the trenches 440 and/or the BvS430 may differ in scale or configuration-for example, with respect to each other and/or with respect to other structures in the system 400. In an embodiment, cylindrical pins (not shown) may be secured to the grooves 440 and extend outward perpendicular to the side surfaces 420 so that the molded plastic lens array may be attached to the system 400 with high accuracy using these alignment pins.

Techniques and architectures for providing a reflective target area for an integrated circuit die assembly are described herein. In the description above, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of certain embodiments. It will be apparent, however, to one skilled in the art that certain other embodiments may be practiced without these specific details. In other instances, structures and devices are shown in block diagram form in order to avoid obscuring the description.

Reference in the specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment.

Some portions of the detailed descriptions in this application are presented in terms of algorithms and symbolic representations of operations on data bits within a computer memory. These algorithmic descriptions and representations are the means used by those skilled in the computer arts to most effectively convey the substance of their work to others skilled in the art. An algorithm is here, and generally, conceived to be a self-consistent sequence of steps leading to a desired result. The steps are those requiring physical manipulations of physical quantities. Usually, though not necessarily, these quantities take the form of electrical or magnetic signals capable of being stored, transferred, combined, compared, and otherwise manipulated. It has proven convenient at times, principally for reasons of common usage, to refer to these signals as bits, values, elements, symbols, characters, terms, numbers, or the like.

It should be borne in mind, however, that all of these and similar terms are to be associated with the appropriate physical quantities and are merely convenient labels applied to these quantities. Unless specifically stated otherwise as apparent from the following discussions, it is appreciated that throughout the specification discussions utilizing terms such as "processing," "computing," "calculating," "determining," "displaying," or the like, refer to the action and processes of a computer system, or similar electronic computing device, that manipulate and/or transform data represented as physical, such as electronic, quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories, registers or other such information storage, transmission or display devices.

Certain embodiments also relate to an apparatus for performing the operations herein. This apparatus may be specially constructed for the required purposes, or it may comprise a general-purpose computer selectively activated or reconfigured by a computer program stored in the computer. Such a computer program may be stored in a computer readable storage medium, such as, but is not limited to, any type of disk including floppy disks, optical disks, CD-ROMs, and magnetic-optical disks, read-only memories (ROMs), Random Access Memories (RAMs) such as dynamic RAM (dram), EPROMs, EEPROMs, magnetic or optical cards, or any type of media suitable for storing electronic instructions, and each coupled to a computer system bus.

The algorithms and displays presented herein are not inherently related to any particular computer or other apparatus. Various general-purpose systems may be used with programs in accordance with the teachings herein, or it may prove convenient to construct more specialized apparatus to perform the required method steps. The required structure for a variety of these systems will appear from the description of the present application. In addition, some embodiments are not described with reference to any particular programming language. It will be appreciated that a variety of programming languages may be used to implement the teachings of certain embodiments as described herein.

Many modifications may be made to the disclosed embodiments and implementations of the invention in addition to those described in this application without departing from their scope. Accordingly, the description and examples herein should be construed in an illustrative, and not a restrictive sense. The scope of the invention should be measured solely by reference to the claims that follow.

Claims (26)

1. An apparatus, comprising:

a reflector die, comprising:

one or more side surfaces, including a first side surface;

a coupling surface coupling the reflector die;

a bevel surface formed by a bevel relative to a coupling surface and a first side surface, the bevel surface providing a target area for an optical signal, wherein the bevel surface and the one or more side surfaces define one or more edges of the coupling surface;

one or more grooves in the coupling surface, each of the one or more grooves extending through a respective one of the ramp surface and the one or more side surfaces, each of the one or more grooves receiving a respective alignment pin for aligning the target area; and

a reflective coating disposed on the beveled surface, the reflective coating for reflecting the optical signal.

2. The apparatus of claim 1, the reflector die further comprising a bonding structure coupled to the coupling surface.

3. The apparatus of claim 2, further comprising:

a photodetector die coupled to the coupling surface via the bonding structure, the photodetector die to receive the reflected optical signal, the photodetector die further to convert the optical signal to an electrical signal.

4. The apparatus of claim 2, wherein the reflector die further comprises one or more traces disposed on the coupling surface, the one or more traces coupled to the bonding structures.

5. The apparatus of claim 4, further comprising:

a photodetector die coupled to the coupling surface, the photodetector die to receive the reflected optical signal, the photodetector die further to convert the optical signal to an electrical signal, wherein the one or more traces convey the electrical signal from the photodetector.

6. The apparatus of claim 4, further comprising:

an amplifier die coupled to the one or more traces to receive and amplify electrical signals.

7. A method, comprising:

etching in the coupling surface of the reflector die substrate:

one or more alignment trenches; and

a bevel groove;

depositing a reflective coating on a surface of the bevel groove; and

after etching, cutting the reflector die from the reflector die substrate, the cutting forming one or more side surfaces defining one or more edges of a coupling surface, the cutting including performing a cut to form a first side surface of the one or more side surfaces, the cut bisecting the bevel trench to form a bevel relative to the coupling surface and the first side surface, the bevel including a bevel surface having the reflective coating deposited thereon, wherein the one or more alignment trenches extend through respective ones of the bevel surface and the one or more side surfaces, respectively.

8. The method of claim 7, further comprising depositing a bonding structure to the coupling surface.

9. The method of claim 8, further comprising bonding a photodetector die to the coupling surface via the bonding structure.

10. The method of claim 9, wherein the bonding the photodetector die comprises aligning the bevel surface with the photodetector die, the aligning comprising leveraging the reflector die via the one or more alignment grooves.

11. The method of claim 8, further comprising depositing one or more traces on the coupling surface, the one or more traces coupled to the bonding structure.

12. The method of claim 11, further comprising bonding a photodetector die to the coupling surface, including coupling the photodetector die to the one or more traces via the bonding structure.

13. The method of claim 11, further comprising bonding an amplifier die to the coupling surface, including coupling an amplifier die to the one or more traces via the bonding structure.

14. A computer-readable storage medium having instructions stored thereon, which when executed by one or more processors, cause the one or more processors to perform a method, the method comprising:

etching in the coupling surface of the reflector die substrate:

one or more alignment trenches; and

a bevel groove;

depositing a reflective coating on a surface of the bevel groove; and

after etching, cutting the reflector die from the reflector die substrate, the cutting forming one or more side surfaces defining one or more edges of a coupling surface, the cutting including performing a cut to form a first side surface of the one or more side surfaces, the cut bisecting the bevel trench to form a bevel relative to the coupling surface and the first side surface, the bevel including a bevel surface having the reflective coating deposited thereon, wherein the one or more alignment trenches extend through respective ones of the bevel surface and the one or more side surfaces, respectively.

15. The computer-readable storage medium of claim 14, wherein the method further comprises depositing a bonding structure to the coupling surface.

16. The computer-readable storage medium of claim 15, wherein the method further comprises bonding a photodetector die to the coupling surface via the bonding structure.

17. The computer-readable storage medium of claim 16, wherein the bonding the photodetector die comprises aligning the bevel surface with the photodetector die, the aligning comprising leveraging the reflector die via the one or more alignment grooves.

18. The computer-readable storage medium of claim 15, the method further comprising depositing one or more traces on the coupling surface, the one or more traces coupled to the bonding structure.

19. The computer-readable storage medium of claim 18, the method further comprising bonding a photodetector die to the coupling surface, including coupling the photodetector die to the one or more traces via the bonding structure.

20. The computer-readable storage medium of claim 18, the method further comprising bonding an amplifier die to the coupling surface, including coupling an amplifier die to the one or more traces via the bonding structure.

21. A system, comprising:

a reflector die, comprising:

one or more side surfaces, including a first side surface;

a coupling surface coupling the reflector die;

a bevel surface formed by a bevel relative to a coupling surface and a first side surface, the bevel surface providing a target area for an optical signal, wherein the bevel surface and the one or more side surfaces define one or more edges of the coupling surface;

one or more grooves in the coupling surface, each of the one or more grooves extending through a respective one of the ramp surface and the one or more side surfaces, each of the one or more grooves receiving a respective alignment pin for aligning the target area; and

a reflective coating disposed on the beveled surface, the reflective coating for reflecting the optical signal; and

a circuit board coupled to the reflector die for exchanging one or more signals based on the optical signal.

22. The system of claim 21, wherein the reflector die further comprises a bonding structure coupled to the coupling surface.

23. The system of claim 22, further comprising:

a photodetector die coupled to the coupling surface via the bonding structure, the photodetector die to receive the reflected optical signal, the photodetector die further to convert the optical signal to an electrical signal.

24. The system of claim 22, wherein the reflector die further comprises one or more traces disposed on the coupling surface, the one or more traces coupled to the bonding structure.

25. The system of claim 24, further comprising:

a photodetector die coupled to the coupling surface, the photodetector die to receive the reflected optical signal, the photodetector die further to convert the optical signal to an electrical signal, wherein the one or more traces convey the electrical signal from the photodetector.

26. The system of claim 24, further comprising:

an amplifier die coupled to the one or more traces to receive and amplify electrical signals.