Optical computing module and optical computing array based on germanium absorption layer

Abstract

The application belongs to the technical field, and particularly relates to a kind of optical computing module and optical computing array based on germanium absorption layer, comprising: cross arrangement input optical waveguide and electric bus, the input end of input optical waveguide is provided with optical splitter, the output end of optical splitter is connected with the first input end of optoelectronic signal processing unit through transmission optical waveguide, the output end of optoelectronic signal processing unit is connected with electric bus, and it is completely different from the scheme of discrete optical computing unit in prior art, an independent optoelectronic signal processing unit is used in the application, which can realize the fast conversion of unmodulated optical signal to electrical signal, the size of the device is basically unchanged compared with the existing technology, and the size of single optical computing unit can be smaller, so that a larger scale matrix can be realized compared with the existing scheme, and the wiring problem of existing discrete devices is avoided, the service life is the same as conventional silicon-based devices, and the frequent switching demand of training level can be met.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of semiconductor optoelectronic devices, and particularly relates to a light computing module based on a germanium absorption layer and a light computing array. BACKGROUND

[0002] Light computing technology has become an important research direction for breaking through the limitations of traditional computing due to its high parallelism, low latency, and potential high energy efficiency. However, existing light computing schemes still have significant challenges in device structure, power consumption, and trainability, which limit their application in large-scale computing and training tasks.

[0003] Currently, the core structure of a light computing unit is usually based on a combination of a modulator and a detector, where the modulator is responsible for encoding or computing operations on optical signals, and the detector completes photoelectric conversion. This discrete design makes it difficult to further optimize the area and power consumption of a single computing unit, which in turn limits the integration scale and energy efficiency of the light computing chip. Specifically, the above-mentioned discrete prior art scheme has the following limitations:

[0004] 1. Light computing architecture based on phase change material (for example, the applicant's prior application file CN118394171B): the switching speed of the phase change material is limited, which is difficult to meet the demand of high-frequency weight update in training tasks; and when frequently switching, the dynamic power consumption will increase significantly, resulting in a decrease in overall energy efficiency.

[0005] 2. Light computing architecture based on carrier absorption (for example, prior art CN109960310A): its power consumption is high, mainly due to the carrier injection loss when the modulator is forward biased, and the combination of discrete modulators and detectors further increases the unit area, limiting the integration density.

[0006] That is, the above-mentioned discrete design scheme is limited in size and has high power consumption.

[0007] Therefore, there is an urgent need for a light computing unit that can meet the requirements of high-frequency switching, low power consumption, and large-scale integration while ensuring computing accuracy. SUMMARY

[0008] The purpose of the present application is to provide a light computing module based on a germanium absorption layer and a light computing array to partially alleviate or solve the above-mentioned deficiencies and meet the requirements of high-frequency switching, low power consumption, and large-scale integration.

[0009] In order to solve the above-mentioned technical problems, the present application specifically adopts the following technical solutions:

[0010] The first aspect of the present application is to provide a light computing module based on a germanium absorption layer, comprising:

[0011] The input optical waveguide and the electric bus are cross arranged, the input end of the input optical waveguide is provided with a light splitter, the output end of the light splitter is connected with the first input end of an optoelectronic signal processing unit through a transmission optical waveguide, and the electric output end of the optoelectronic signal processing unit is connected with the electric bus;

[0012] The photoelectric characteristic of the light absorption layer in the optoelectronic signal processing unit can be changed by the second input end writing control signal, the optoelectronic signal processing unit can convert the light signal inputted by the first input end into a corresponding current signal, and send the current signal to the electric bus through the electric output end; the photoelectric characteristic includes the light absorption coefficient of the light absorption layer;

[0013] The product of the multiplier value and the multiplicand value is encoded in the current signal;

[0014] The optoelectronic signal processing unit comprises a silicon substrate and an insulating layer deposited on the silicon substrate; the insulating layer is provided with a waveguide layer; the waveguide layer is embedded with a germanium absorption layer.

[0015] As an improvement, the optoelectronic signal processing unit uses pure germanium as the light absorption layer;

[0016] The first depth of the embedding of the germanium absorption layer in the waveguide layer is greater than the thickness of the waveguide layer.

[0017] As an improvement, the top and / or bottom of the germanium absorption layer is provided with a heating unit, and the heating unit extends along the length direction of the germanium absorption layer; or,

[0018] The two sides of the germanium absorption layer are respectively provided with a heating unit, and the heating unit extends along the length direction of the germanium absorption layer; or,

[0019] The two sides of the germanium absorption layer are respectively provided with a heating unit group, and each side of the heating unit group comprises a plurality of heating units uniformly spaced along the length direction of the germanium absorption layer, wherein the heating levels of the adjacent two heating units on the same side are first heating and second heating respectively.

[0020] As an improvement, the germanium absorption layer comprises a light guiding region and a light absorption region arranged in sequence along the light propagation direction,

[0021] The cross-sectional area of the light guiding region gradually increases from the incident end along the direction close to the light absorption region; the cross-sectional area of the light absorption region is the same along the light propagation direction.

[0022] As an improvement, the light guiding region has a width gradually increasing along the light propagation direction from the incident end when viewed from above; and the light guiding region has a width gradually decreasing from the top to the bottom when viewed from the side; or, the interface between the light guiding region and the waveguide layer is in the shape of a sector; and / or, the light absorbing region is in the shape of a rectangle when viewed from the side.

[0023] The second aspect of the present application provides a germanium-absorbing-layer-based optical computing array, comprising:

[0024] A crossbar switch matrix architecture formed by a plurality of rows of input optical waveguides parallel to each other and a plurality of columns of electrical buses parallel to each other; optical input signals are transmitted through the input optical waveguides;

[0025] A plurality of optical splitters arranged at the front end of each intersection node of a row of optical input waveguides and a column of electrical buses;

[0026] A plurality of optoelectronic signal processing units, each corresponding to an intersection node, and the first input end of the optoelectronic signal processing unit is connected to the output end of the optical splitter through a transmission optical waveguide, and the electrical output end of the optoelectronic signal processing unit is connected to the electrical bus in the corresponding intersection node;

[0027] Wherein, the optoelectronic properties of the germanium-absorbing layer in the optoelectronic signal processing unit can be changed by a control signal input through the second input end, and the optoelectronic signal processing unit can convert the optical signal input through the first input end into a corresponding current signal and send it to the electrical bus through the electrical output end; the optoelectronic properties include the optical absorption coefficient; and the product of the multiplier value and the multiplicand value is encoded in the current signal;

[0028] The optoelectronic signal processing unit comprises a silicon substrate and an insulating layer deposited on the silicon substrate; the insulating layer is provided with a waveguide layer; and the waveguide layer is embedded with a germanium-absorbing layer.

[0029] As an improvement, the optoelectronic signal processing unit uses pure germanium as the light absorbing layer; and the first depth of the germanium-absorbing layer embedded in the waveguide layer is greater than the thickness of the waveguide layer.

[0030] As an improvement, the top and / or bottom of the germanium-absorbing layer is provided with a heating unit extending along the length direction of the germanium-absorbing layer; or, the two sides of the germanium-absorbing layer are respectively provided with a heating unit, and the heating unit extends along the length direction of the germanium-absorbing layer; or, the two sides of the germanium-absorbing layer are respectively provided with a heating unit group, and each heating unit group on one side includes a plurality of heating units uniformly spaced along the length direction of the germanium-absorbing layer, wherein the heating levels of the adjacent two heating units on the same side are first heating and second heating, respectively.

[0031] As an improvement, the germanium absorption layer comprises a light guiding region and an absorption region arranged in sequence along the light propagation direction, wherein the cross-sectional area of the light guiding region gradually increases from the incident end along the direction close to the light absorption region; the cross-sectional area of the light absorption region is the same along the light propagation direction.

[0032] As an improvement, the second input end of each photoelectric signal processing unit is connected with a Pad, and a Pad is arranged on each column of the electric bus; and / or, an EOM is arranged on each row of the input light waveguide.

[0033] The principles and beneficial technical effects of the present application are that:

[0034] The present application adopts independent photoelectric signal processing units to simultaneously realize modulation and detection. Specifically, the optical signal input into the photoelectric signal processing unit is not modulated and is a stable value. When the optical signal is processed by the photoelectric signal processing unit, the part of the optical signal that is absorbed is directly converted into a current signal as output for summation operation, without the need to separately convert the unabsorbed optical signal (i.e. the remaining optical signal) into an electrical signal by a detector. Moreover, the size of the photoelectric signal processing unit remains basically unchanged compared with the size of the detector device in the prior art, which can make the size of a single optical computing module smaller, thereby realizing a larger scale matrix compared with the prior art, and avoiding the problems of difficult wiring and large size caused by the discrete structure of modulator + detector in the prior art (the discrete structure first modulates the optical signal by a modulator, and then inputs the modulated optical signal into a detector to convert it into an electrical signal), which is not conducive to large-scale integration. In addition, the service life of the photoelectric signal processing unit in the present application is the same as that of the conventional silicon-based device, which can meet the frequent switching requirements of the training level. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, each element or part is not necessarily drawn according to the actual proportion. Obviously, the drawings described below are some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without any creative labor.

[0036] Figure 1 It is a side view structural schematic diagram of the prior art;

[0037] Figure 2 It is a side view structural schematic diagram of the fourth embodiment of the present application;

[0038] Figure 3Top view schematic of embodiment four of the present application;

[0039] Figure 4 Top view of the gradual section in embodiment four of the present application;

[0040] Figure 5 Side view of one exemplary modulator in embodiment three of the present application;

[0041] Figure 6 Side view of another exemplary modulator in embodiment three of the present application;

[0042] Figure 7 Side view of yet another exemplary modulator in embodiment three of the present application;

[0043] Figure 8 Top view of a modulator in embodiment three of the present application;

[0044] Figure 9 Elevational view of the germanium absorption layer in embodiment three and the germanium strip in embodiment four of the present application;

[0045] Figure 10 Top view of the germanium absorption layer in embodiment three and the germanium strip in embodiment four of the present application;

[0046] Figure 11 Schematic of a light computing module in embodiment one of the present application;

[0047] Figure 12 Schematic of a light computing array in embodiment two of the present application;

[0048] Figure 13 Schematic of another light computing array in embodiment two of the present application;

[0049] Figure 14 Schematic of yet another light computing array in embodiment two of the present application;

[0050] Figure 15 Schematic of a light computing module in embodiment five of the present application;

[0051] Figure 16 Schematic of signal comparison by the detection unit in embodiments five through seven of the present application;

[0052] Figure 17 Flow chart of the detection method in embodiment seven of the present application.

[0053] Marked in the figure: 1, silicon substrate; 2, insulating layer; 3, ridge type optical waveguide / waveguide layer; 31, silicon ridge; 32, flat plate layer; 4, electrode; 5, germanium band / germanium absorption layer; 51, gradual section / light guiding area; 52, straight section / light absorbing area; 6, silicon band; 7, heating unit; 101, photoelectric signal processing unit; 102, input optical waveguide; 103, transmission optical waveguide; 104, transmission optical waveguide; 105, optical splitter. DETAILED DESCRIPTION

[0054] In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0055] Herein, using suffixes such as "module", "component" or "unit" for representing elements is only for facilitating the description of the present application, and has no specific meaning by itself. Therefore, "module", "component" or "unit" can be used mixedly. Herein, the terms "upper", "lower", "inner", "outer", "front", "back", "one end", "the other end" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for facilitating the description of the present application and simplifying the description, and do not indicate or imply that the indicated device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0056] Herein, unless otherwise explicitly specified and limited, the terms "mount", "provided with", "connected" and the like should be understood broadly, for example, "connected" can be fixedly connected, can be detachably connected, or integrally connected; can be mechanically connected, can be directly connected, or indirectly connected through an intermediate medium, can be the communication inside two elements. For a person of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances. Herein, "a plurality of" means two or more, that is, it includes two, three, four, five and the like.

[0057] Herein, the "optical splitter" can utilize components such as optical waveguide, optical coupler, heater, phase shifter and the like with specific structures to realize the distribution of optical signals inside the chip in an active or passive manner.

[0058] In this paper, Pad is used for transmitting electrical signals or optical signals in optical computing units or electrical buses; EMO is an optical modulator based on electro-optic effect, which controls the power, phase and polarization of laser beams through electronic control signals, and is used to preliminarily modulate the input optical signal, so as to provide an optical signal conforming to the processing range of the optical signal processing unit.

[0059] Embodiment one

[0060] The embodiment provides an optical computing unit, comprising:

[0061] The input optical waveguide and the electrical bus are cross-connected, the input end of the input optical waveguide is provided with an optical splitter, the output end of the optical splitter is connected with the first input end of an optoelectronic signal processing unit through a transmission optical waveguide, and the electrical output end of the optoelectronic signal processing unit is connected with the electrical bus.

[0062] The optoelectronic signal processing unit can convert the optical signal input through the first input end into a corresponding current signal and send it to the electrical bus through the electrical output end, and the optoelectronic property of the optical absorption layer in the optoelectronic signal processing unit can be changed through the second input end write control signal; the optoelectronic property includes the optical absorption coefficient of the optical absorption layer.

[0063] The product of the multiplier value and the multiplicand value is encoded in the current signal.

[0064] The optical computing unit in the prior art adopts a combination of discrete modulators and detectors, part of the optical signal in the input modulator is absorbed, the part of the optical signal (remaining optical signal) that is not absorbed is output from the optical output end of the modulator and enters the detector to be converted into an electrical signal, and then enters the data terminal for processing; the optical computing unit in the present application is completely different from the above scheme, which adopts an independent optoelectronic signal processing unit, which directly converts the absorbed part of the optical signal into an electrical signal as output for summation operation and then inputs the data terminal for data processing, without additional processing of the remaining optical signal, so as to directly obtain the processed electrical signal.

[0065] The size of the optoelectronic signal processing unit in the present application is basically unchanged compared with the size of the detector device in the prior art, so that the size of a single optical computing unit can be smaller, thereby realizing a larger scale matrix compared with the prior art, and avoiding the wiring difficulty problem of the existing discrete devices, and the service life performance is the same as that of the conventional silicon-based device, which can meet the frequent switching demand of the training level.

[0066] Embodiment two

[0067] The embodiment provides an optical computing array, comprising a plurality of optical computing modules in the embodiment one, comprising:

[0068] a crossbar switch matrix architecture formed by a plurality of rows of input optical waveguides and a plurality of columns of electrical buses crossing each other; optical input signals are transmitted through the input optical waveguides;

[0069] a plurality of optical splitters arranged at the front end of each intersection node of a row of optical input waveguides and a column of electrical buses;

[0070] a plurality of optoelectronic signal processing units, each of which corresponds to one of the intersection nodes, and a first input end of the optoelectronic signal processing unit is connected to an output end of the optical splitter through a transmission optical waveguide, and an electrical output end of the optoelectronic signal processing unit is connected to the electrical bus in the corresponding intersection node;

[0071] wherein the optoelectronic properties of the optical absorption layer in the optoelectronic signal processing unit can be changed by a write control signal input through a second input end, and the optoelectronic signal processing unit can convert the optical signal input through the first input end into a corresponding current signal and send it to the electrical bus through the electrical output end; the optoelectronic properties include the optical absorption coefficient;

[0072] wherein the product of the multiplier value and the multiplicand value is encoded in the current signal.

[0073] In some embodiments, the second input end of each of the optoelectronic signal processing units is connected to a Pad, and a Pad is arranged on each of the electrical buses; and / or, an EOM is arranged on each of the input optical waveguides.

[0074] Embodiment Three

[0075] This embodiment provides an optoelectronic signal processing unit which uses pure germanium as an optical absorption layer, as an example of the optoelectronic signal processing unit in Embodiment One and / or Embodiment Two:

[0076] The optoelectronic signal processing unit comprises a silicon substrate and an insulating layer deposited on the silicon substrate; a waveguide layer is arranged on the insulating layer; a germanium absorption layer is embedded in the waveguide layer; the first depth of embedding the germanium absorption layer in the waveguide layer is less than the thickness of the waveguide layer (at this time, it is "shallow etching"), or the second depth of embedding the germanium absorption layer in the waveguide layer is equal to the thickness of the waveguide layer (at this time, it is "full etching").

[0077] In the above embodiments, when the second depth is equal to the thickness of the waveguide layer 3, i.e., the insulating layer 2 is taken as the etching end point, on the one hand, the germanium absorption layer 5 has a larger cross section, so that the time of the modulation region coinciding with the light field is the longest. In the same length, the responsivity is higher; in the same responsivity, the size is the smallest. On the other hand, the etching depth is easy to control, which can ensure the consistency of the etching groove depth between different modulators. In the traditional shallow etching process, due to the shallow etching depth and the difficulty in accurate control, the etching depth is easily affected by the uneven thickness of the silicon layer, resulting in inconsistent etching depth, and further affecting the performance uniformity of the modulator. The etching groove process reaching the insulating layer 2 has better stability, which is conducive to large-scale production of high-quality modulators.

[0078] In some embodiments, the first depth of the waveguide layer can also be greater than the thickness of the waveguide layer, which is "over-etching".

[0079] In some embodiments, at least one side of the germanium absorption layer 5 is provided with a heating unit 7.

[0080] In some specific embodiments, the top and / or bottom of the germanium absorption layer 5 is provided with a heating unit 7, and the heating unit 7 extends along the length direction of the germanium absorption layer 5; or, the two sides of the germanium absorption layer 5 are respectively provided with a heating unit 7, and the heating unit 7 extends along the length direction of the germanium absorption layer 5; or, the two sides of the germanium absorption layer 5 are respectively provided with a heating unit 7 group, and each heating unit 7 group on the same side includes a plurality of heating units 7 uniformly spaced along the length direction of the germanium absorption layer 5, wherein the heating levels of the adjacent two heating units 7 on the same side are first heating and second heating, respectively. The heating unit 7 is used to change the photoelectric property of the light absorption layer.

[0081] Unlike the traditional idea of relying on high electric field intensity to improve the absorption coefficient to ensure the uniformity of the photoelectric current density, the present application provides a thermal compensation mechanism only for the end point effect. Specifically, by providing a heating unit 7 on at least one side (bottom and / or top, or front and back) of the germanium absorption layer 5, the heating unit 7 acts on the germanium absorption layer 5 along the length direction of the germanium absorption layer, ensuring the consistency and uniformity of the temperature of the entire germanium absorption layer 5, thereby increasing the transitionable valence band electrons, and further changing the light absorption coefficient of the germanium absorption layer 5 while reducing the operating voltage of the electro-absorption modulator. In this process, only the final light absorption rate (i.e., the ratio of input light to output light / input light) needs to be ensured, and the uniformity of the light absorption coefficient of the germanium absorption layer 5 does not need to be considered.

[0082] That is, the application provides a thermal compensation mechanism for double regulation of the light absorption coefficient only for the end effect. First, the light absorption coefficient of the germanium absorption layer is adjusted by heating the germanium absorption layer to adjust the light absorption coefficient of the germanium absorption layer from the germanium modulator itself. Then, the light absorption coefficient of the germanium absorption layer is further adjusted by adjusting the input voltage. That is, the adjustment requirement of the input voltage is not high, that is, the response speed of the calculation array can be ensured under the condition of low energy consumption, thereby meeting the requirements of large-scale matrix.

[0083] In some embodiments, the germanium modulator further comprises:

[0084] A temperature monitoring module is configured to monitor the actual temperature value of the germanium absorption layer 5 in real time.

[0085] A first judgment module is configured to judge whether the actual temperature value monitored by the temperature monitoring module is greater than a first preset temperature threshold. If the actual temperature value is greater than the first preset temperature threshold, a first control signal representing stopping heating is generated and sent to the heating unit 7 / the heating unit group. If the actual temperature value is less than the first preset temperature threshold, a second control signal representing continuing monitoring is generated and sent to the temperature monitoring module; and / or,

[0086] A temperature monitoring module is configured to monitor the actual temperature value of the germanium absorption layer 5 after being heated by the heating unit 7 with a heating level of one level and in a heating state.

[0087] A second judgment module is configured to judge whether the actual temperature value monitored by the temperature monitoring module for a preset time length reaches a preset target temperature threshold. If not, a third control signal representing starting the heating unit 7 with a heating level of two levels and in a dormant state is generated and sent, so that the actual temperature of the germanium absorption layer 5 reaches the preset target temperature threshold.

[0088] The first temperature threshold can be obtained by a large number of experiments in advance or preset by the user according to experience. When the actual temperature is near the first preset temperature threshold, the number of transition valence electrons tends to be maximized, but at the same time, the material itself will not be adversely affected.

[0089] The division of heating levels (one level and two levels) is only to distinguish between them, and cannot limit their heating power or other characteristics. When only one level of heating is turned on, the heating power is small, and when one level and two levels of heating are turned on at the same time, the heating power increases, and the temperature of the germanium absorption layer 5 can also be correspondingly increased.

[0090] The present application regulates the temperature of the germanium absorption layer 5 through a real-time feedback mechanism, which can maximize the number of transitionable valence band electrons and improve the stability of the temperature of the germanium absorption layer 5, thereby preventing the light signal emitted by the germanium absorption layer 5 from being unstable due to frequent changes in the temperature of the germanium absorption layer 5.

[0091] In some embodiments, the germanium absorption layer comprises a light guiding region and a light absorbing region arranged in sequence along the light propagation direction, wherein the cross-sectional area of the light guiding region gradually increases from the incident end along the direction close to the light absorbing region; and the cross-sectional area of the light absorbing region is the same along the light propagation direction.

[0092] In some specific embodiments, the longitudinal section of the light guiding region 51 is a right trapezoid, and the included angle a between the hypotenuse of the right trapezoid and the base is 86°-89°, wherein the hypotenuse corresponds to the interface between the light guiding region 51 and the waveguide layer 3; the longitudinal section of the light absorbing region 52 is a rectangle; or the interface between the light guiding region 51 and the waveguide layer 3 is a sector. The longitudinal section refers to a vertical plane parallel to the length direction of the germanium absorption layer.

[0093] When viewed from above, the width of the light guiding region gradually increases from the incident end along the light propagation direction; and when viewed from the side, the width of the light guiding region gradually decreases from the top to the bottom; or the interface between the light guiding region and the waveguide layer is a sector; and / or the cross-section of the light absorbing region is a rectangle.

[0094] The purpose of the above arrangement is to achieve smooth transition of the refractive index. The refractive index of silicon is about 3.4, and the refractive index of germanium is about 4.4. By gradually changing the structure, the refractive index can be gradually transitioned from the waveguide layer 3 (silicon waveguide) to germanium, reducing the reflection of light at the incident end. When light propagates in different refractive index media, the greater the difference in refractive index, the more serious the reflection. This gradual transition structure allows light to enter the germanium absorption layer 5 more smoothly, improves the coupling efficiency of light, and thus improves the light absorption capacity of the modulator.

[0095] In an ideal case, the light guiding region is a cone with a small front and a large back. The conical structure can achieve a more perfect refractive index gradient, minimize the reflection of light when entering the germanium absorption layer 5, and theoretically maximize the coupling efficiency of light.

[0096] Due to process limitations, the conical light guiding region requires high cost. Therefore, in order to reduce the process difficulty, the cross-sectional area of the light guiding region is gradually increased from the incident end along the direction close to the light absorbing region 52 in the embodiment, for example, the light guiding region is a front narrow and back wide triangle when viewed from above; and is a trapezoid with large upper and small lower when viewed from the front. Although it is different from the ideal conical shape, the trapezoidal structure still can realize the gradual change of the refractive index to a certain extent, reduce the reflection of light, and is a feasible solution under the existing process conditions.

[0097] That is, by limiting the shape of the light guiding region, the cross-sectional area of the light guiding region gradually increases from the incident end in height and length, which can greatly reduce the reflection of light at the incident end when the light propagates in the light absorbing layer (germanium absorbing layer) with a larger cross-sectional area, and improve the light absorption rate of the modulator. That is, the present application provides a full etching scheme with a thermal compensation mechanism and capable of reducing light reflection.

[0098] In some embodiments, the width and length of the heating unit 7 located at the top and / or bottom of the germanium absorbing layer 5 are smaller than the width and length of the germanium absorbing layer 5. In this way, the heating effect is ensured while unnecessary heat waste is avoided.

[0099] In summary, for the millisecond-level frequent switching requirement in the deep learning training scene, the present application provides a high-response light computing module / computing array with a thermal compensation mechanism and capable of reducing light reflection, so as to realize the design of a low-power large-scale integrated computing array under the condition of meeting the frequent switching.

[0100] Unlike the existing modulation by using phase change material, or changing the light absorption coefficient by injecting current or applying voltage to change the carrier concentration in the doped layer, the present application provides a light computing array based on a reverse-biased germanium modulator, and a scheme for multiple regulation of the light absorption characteristics of the germanium absorbing layer.

[0101] Firstly, the photoelectric signal processing unit with a pure germanium absorbing layer in the present application has extremely low dark current under reverse bias, and the photocurrent during operation is at least 2 orders of magnitude smaller than that of the carrier absorption modulator or the phase change material modulator under forward conduction, thereby effectively reducing the power consumption of the single device during operation.

[0102] Further, the heating unit is arranged on at least one side of the germanium absorbing layer, and is matched with a real-time feedback mechanism to ensure the consistency and uniformity of the temperature of the entire germanium absorbing layer, thereby increasing the transitionable valence band electrons, changing the light absorption coefficient of the germanium absorbing layer, and reducing the operating voltage of the photoelectric signal processing unit.

[0103] Further, in the case of a large light absorption cross-sectional area of the light absorption region (germanium absorption layer) (for example, "full etching"), the present application designs the germanium absorption layer in zones (light guiding zone and light absorption zone), and uses the gradually changing interface formed by the gradual change in height and width of the light guiding zone to guide the light signal transmitted from the optical waveguide, that is, to make the cross-sectional area of the light guiding zone gradually increase in height and length from the incident end, thereby greatly reducing the reflection of the light at the incident end when the light propagates in the light absorption layer (germanium absorption layer) with a larger cross-sectional area, and improving the light absorption rate of the optoelectronic signal processing unit.

[0104] Embodiment Four

[0105] The present embodiment provides an optoelectronic signal processing unit, which uses pure germanium as the light absorption layer, and differs from Embodiment Three in that:

[0106] The optoelectronic signal processing unit comprises a silicon substrate 1 and an insulating layer 2 deposited on the silicon substrate 1; the insulating layer 2 is provided with an optical waveguide; the optical waveguide is provided with an etching groove reaching the insulating layer 2 or embedded in the insulating layer 2; the etching groove is filled with a germanium strip 5 as a light absorption zone, and electrodes 4 are arranged on both sides of the etching groove.

[0107] The bottom of the germanium strip 5 is flush with the upper surface of the insulating layer 2, or the bottom of the germanium strip 5 is embedded in the insulating layer 2, and the top of the germanium strip 5 protrudes from the upper surface of the optical waveguide.

[0108] In the present embodiment, compared with the prior art in Embodiment Three Figure 1 In the prior art of the present application, the etching groove of the optical waveguide reaches the insulating layer 2, that is, the bottom of the etching groove is flush with the insulating layer 2 or embedded in the insulating layer. The bottom of the germanium strip 5 in the etching groove can be flush with the upper surface of the insulating layer, or the bottom of the germanium strip 5 can be embedded in the insulating layer 2, and the top of the germanium strip 5 can protrude from the upper surface of the optical waveguide. The germanium strip 5 has a larger cross-sectional area, so that the time of the detection region coinciding with the light field is the longest. In the same length, the responsivity is higher; in the same responsivity, the size is the smallest.

[0109] In addition, the insulating layer 2 is used as the etching end point, and the etching depth is easy to control, which can ensure the consistency of the etching groove depth between different detectors. In the traditional shallow etching process, the etching depth is shallow and difficult to control accurately, and is easily affected by factors such as uneven silicon layer thickness, resulting in inconsistent etching depth, which further affects the performance uniformity of the detector. The etching groove process reaching the insulating layer has better stability, which is conducive to large-scale production of high-quality detectors.

[0110] More specifically, in this embodiment, the optical waveguide is a ridge-type optical waveguide 3, including a planar layer 32 and a silicon ridge 31 on the planar layer 32; the electrode 4 is disposed on the planar layer 32; and the etching groove penetrates the silicon ridge 31.

[0111] The ridge waveguide 3 utilizes the propagation characteristics of light in media with different refractive indices. The refractive index of the silicon ridge 31 is higher than that of the surrounding environment, thus constraining the light. When light propagates in the ridge waveguide, it is confined to the silicon ridge 31 region, reducing light scattering and loss, improving light transmission efficiency, and providing a stable optical transmission channel for the detector's optical detection process.

[0112] Electrode 4 is placed on the planar layer 32 for easy connection to external circuits. The planar layer 32 provides a large planar area, which is beneficial for the fabrication and layout of electrode 4, ensuring good electrical contact between electrode 4 and external circuits. At the same time, this layout avoids direct interference of electrode 4 with the light propagation path, reduces absorption or scattering of light during propagation due to the presence of electrodes, ensures stable transmission of optical signals in the silicon ridge, and improves the photodetector's optical detection performance.

[0113] The etching trench penetrates the silicon ridge 31, providing ample space for the germanium strip 5. The germanium strip 5, as the light absorption region, is in direct and close contact with the light propagation path. When light propagates in the ridge-shaped waveguide, it passes through the germanium strip 5 within the etching trench. The germanium strip 5 effectively absorbs the light signal, converting it into an electrical signal. The design of the etching trench penetrating the silicon ridge 31 ensures sufficient interaction between the light and the germanium strip 5, enhancing the light absorption effect and thus improving the detector's responsivity and sensitivity to light signals.

[0114] like Figure 3 As shown, in some embodiments, the germanium strip 5 is connected to silicon strips 6 at both ends. For example... Figure 4 As shown, the germanium strip 5 includes a progressive section 51 (also referred to herein as the light guiding region) and a straight section 52 (also referred to herein as the light absorption region); the progressive section 51 is disposed at the incident end of the germanium strip 5, and the cross-sectional area of ​​the progressive section 51 increases along the incident direction of light (i.e., the light propagation direction); the shape of the exit end of the silicon strip 6 is matched and connected to the progressive section 51.

[0115] The purpose of this design is to achieve a smooth transition in refractive index. Since silicon has a refractive index of approximately 3.4 and germanium approximately 4.4, this gradual structural change allows the refractive index to transition gradually from silicon to germanium, reducing light reflection at the incident end. When light propagates at the interface of media with different refractive indices, the greater the difference in refractive index, the more severe the reflection. This gradual transition structure allows light to enter the germanium band more smoothly from the silicon waveguide, improving the coupling efficiency and thus enhancing the detector's absorption capability.

[0116] In an ideal case, the gradual section 51 is a front-small and rear-large conical shape, which can achieve a more perfect refractive index gradient, minimize the reflection of light when entering the germanium strip, and theoretically maximize the coupling efficiency of light and the responsivity of the detector.

[0117] Due to process limitations, the conical gradual section 51 needs to pay a high cost. Therefore, in order to reduce the process difficulty, the gradual section 51 in this embodiment is a front-narrow and rear-wide triangle in plan view and a large-top and small-bottom trapezoid in elevation view, as shown in Figure 4 、 Figure 5 Although it is different from the ideal conical shape, the trapezoidal structure can still achieve a certain degree of refractive index gradient and reduce light reflection, which is a feasible solution under the existing process conditions. More preferably, the length of the gradual section 51 along the light propagation direction is the same as the length of the straight section 52 along the light propagation direction.

[0118] In some other embodiments, a silicon-germanium alloy transition layer is also provided between the incident end of the germanium strip 5 and the silicon strip 6, and the silicon-germanium alloy transition layer is gradiently doped, with the germanium concentration increasing from the silicon strip side to the germanium strip side. The germanium concentration increases from 10% on the silicon strip side to 100% on the germanium strip side. By providing the silicon-germanium alloy transition layer and increasing the germanium concentration from 10% on the silicon strip 6 side to 100% on the germanium strip side, the refractive index can be gradually transitioned from the refractive index of silicon to the refractive index of germanium. In the transition layer, as the germanium concentration increases, its refractive index also gradually increases, forming a refractive index gradient region between the silicon strip and the germanium strip. In this way, during the propagation of light, the reflection caused by the sudden change of refractive index is reduced, so that the light can more smoothly enter the germanium strip from the silicon strip, improving the coupling efficiency of light.

[0119] In addition, the electrode 4 in this embodiment is a metal electrode made of copper or aluminum. Copper and aluminum have good processing performance in semiconductor manufacturing processes. They can be deposited by various common process methods, such as sputtering in physical vapor deposition (PVD), electron beam evaporation, etc., to form the required electrode pattern. In the photolithography and etching process, the shape and size of the electrode can also be accurately defined to meet the design requirements of the detector. Moreover, these materials are widely used in industrial production, and the related process equipment and technology are mature, which is convenient for large-scale production and reduces production costs.

[0120] The application improves the responsivity of the photoelectric signal processing unit by increasing the light absorption area, and realizes the miniaturization of the device, thereby facilitating large-scale integration. Specifically, an etching groove is etched on the waveguide in a full etching or over-etching manner, thereby increasing the light absorption area (i.e. the cross-sectional area) along the light propagation direction, and further improving the light absorption rate, significantly improving the responsivity of the photoelectric signal processing unit, and making it better meet the demand for high-sensitivity detection of optical signals, without the need to increase the length of the germanium band, and being more conducive to the miniaturization of the device.

[0121] In addition, the application improves the poor process stability. In the prior art shallow etching, on the one hand, the process itself cannot be completely consistent every time, and on the other hand, the slight difference in the thickness of the silicon layer may lead to different etching depths, affecting the consistency of the performance indicators such as the dark current and the responsivity of the photoelectric signal processing unit. In the application, the etching groove reaches the insulating layer, and the insulating layer is used as a stable etching stop layer, which greatly reduces the sensitivity of the process to the change in the thickness of the silicon layer, improves the process stability, and makes the performance of the produced photoelectric signal processing unit more stable and uniform.

[0122] The application avoids the performance loss caused by light leakage. In the traditional shallow etching structure, when the light propagates in the germanium / silicon processing area, it is easy to leak to the bottom of the shallow etching groove, reducing the overlap time of the light field and the germanium, and affecting the processing efficiency. In the application, the design of the etching groove reaching the insulating layer optimizes the light propagation path, reduces the light leakage, ensures the full action of the light field and the germanium band, and improves the comprehensive performance of the photoelectric signal processing unit.

[0123] In addition, in the application, the light absorption area is increased from the cross-sectional view, so that when the light is incident to the interface between the germanium band and the silicon, the amount of reflected light will also increase. Therefore, by changing the gradual structure of the silicon band and the germanium band, the refractive index can be gradually transitioned from the silicon waveguide to the germanium, reducing the reflection of the light at the incident end. When the light propagates at the interface of different refractive index media, the greater the difference in refractive index, the more serious the reflection. This gradual transition structure can make the light enter the germanium band from the silicon waveguide more smoothly, improve the coupling efficiency of the light, and further improve the absorption capacity of the detector to the light.

[0124] Embodiment five

[0125] The embodiment provides a light computing module with a self-detection function, which is shown in Figure 15 , and includes:

[0126] The input light waveguide and the output electrical bus are cross-connected, the input end of the input light waveguide is provided with a light splitter, the output end of the light splitter is connected with the first input end of a photoelectric signal processing unit through a transmission light waveguide, and the photoelectric signal processing unit is further provided with a second input end for inputting an external electrical driving signal.

[0127] The electrical output end of the optoelectronic signal processing unit is connected with the electrical bus;

[0128] The optical output end of the optoelectronic signal processing unit is connected with a detection unit, and the detection unit comprises a detector and a data processing unit connected in sequence;

[0129] The optical input end of the detector is connected with the optical output end of the optoelectronic signal processor, a first input end for inputting the electrical driving signal is arranged on the data processing unit, and a second input end of the data processing unit is connected with the electrical output end of the detector.

[0130] The data processing unit is used for analyzing the electrical driving signal and the output electrical signal output by the detector to obtain an analysis result, and the data processing unit can be an upper computer.

[0131] The first input end of the optoelectronic signal processing unit is an optical input end, and the second input end is an electrical input end; the optical signal entering the optoelectronic signal processing unit through the optical input end is modulated by the electrical driving signal input through the electrical input end, the part of the optical signal absorbed is converted into an electrical signal and output to the electrical bus, and the other part of the optical signal (remaining optical signal) not absorbed is conducted to the optical output end and enters the detector in the detection unit.

[0132] In some embodiments, the detection unit further comprises a comparator arranged between the detection unit and the detector, wherein a first input end for inputting the electrical driving signal is arranged on the comparator, a second input end of the comparator is connected with the electrical output end of the detector, and an output end of the comparator is connected with the data processing unit.

[0133] Therefore, the application provides an optical computing module with an independent detection unit, uses the remaining optical signal in the optical computing module to directly generate an output electrical signal corresponding to the remaining optical signal, then synchronously outputs the output electrical signal and the electrical driving signal to an external correction unit for comparison, and directly obtains the distortion between the two; compared with the prior art of inserting error correction codes in the calculation data signal to improve the calculation accuracy, the application improves the hardware structure, on the one hand, the cost is low, and the calculation amount is small, on the other hand, the remaining optical signal (not the output electrical signal) is used for error correction, and the entire error correction process is independent, and does not affect other components or signals in the optical computing module except the detection unit.

[0134] In some embodiments, the photoelectric signal processing unit can be the photoelectric signal processing unit in Embodiment Three, specifically, the photoelectric signal processing unit comprises: a silicon substrate and an insulating layer deposited on the silicon substrate; the insulating layer is provided with a waveguide layer; the waveguide layer is embedded with a germanium absorption layer; the first depth of the germanium absorption layer embedded in the waveguide layer is less than the thickness of the waveguide layer, or the second depth of the germanium absorption layer embedded in the waveguide layer is equal to the thickness of the waveguide layer.

[0135] The top and / or bottom of the germanium absorption layer is provided with a heating unit extending along the length direction of the germanium absorption layer; or, the two sides of the germanium absorption layer are respectively provided with a heating unit extending along the length direction of the germanium absorption layer; or, the two sides of the germanium absorption layer are respectively provided with a heating unit group, and each side of the heating unit group comprises a plurality of heating units uniformly spaced along the length direction of the germanium absorption layer, wherein the heating levels of the adjacent two heating units on the same side are first heating and second heating respectively.

[0136] In summary, the present application actually provides an error correction scheme for "amplifying" the residual light signal and detecting by using an independent detection unit.

[0137] In the present application, the photoelectric signal processing unit is improved in structure, pure germanium is used as the absorption layer of the photoelectric signal processor, and a heat compensation mechanism for double regulation of the light absorption coefficient is provided, specifically, the light absorption coefficient of the germanium absorption layer is adjusted from the germanium modulator itself by heating the germanium absorption layer, and then the light absorption coefficient of the germanium absorption layer is further adjusted by adjusting the input voltage, which requires a low adjustment of the input voltage, that is, the response speed of the calculation module can be greatly improved under the condition of ensuring low energy consumption, in other words, the residual light signal and the output electrical signal in the calculation module can be "amplified" to a certain extent.

[0138] Further, the "amplified" residual light signal is used for error correction analysis, the "amplified" distortion can be obtained, and the case that the distortion degree is small and difficult to detect can also be avoided.

[0139] In other embodiments, the photoelectric signal processing unit can also be the photoelectric signal processing unit in Embodiment Four, specifically, the photoelectric signal processing unit comprises: a silicon substrate and an insulating layer deposited on the silicon substrate; the insulating layer is provided with a waveguide layer (also referred to as an optical waveguide); the waveguide layer is provided with an etching groove reaching the insulating layer or embedded in the insulating layer; the etching groove is filled with a germanium absorption layer (also referred to as a germanium strip) as a light absorption area, and electrodes are arranged on both sides of the etching groove;

[0140] The bottom of the germanium absorption layer is flush with the upper surface of the insulating layer, or the bottom of the germanium absorption layer is embedded in the insulating layer; and the top of the germanium absorption layer protrudes from the upper surface of the waveguide layer.

[0141] In some embodiments, the germanium absorption layer comprises a light guiding region and a light absorption region arranged in sequence along the light propagation direction, wherein the cross-sectional area of the light guiding region gradually increases from the incident end along the direction close to the light absorption region; and the cross-sectional area of the light absorption region is the same along the light propagation direction.

[0142] In some embodiments, the width of the light guiding region gradually increases from the incident end along the light propagation direction when viewed from the top; and the width of the light guiding region gradually decreases from the top to the bottom when viewed from the side; or the interface between the light guiding region and the waveguide layer is fan-shaped; and / or the light absorption region is rectangular when viewed from the side.

[0143] In summary, the present application also provides an error correction scheme for "amplifying" the residual light signal and detecting by using an independent detection unit.

[0144] The difference between the above scheme and the present scheme is that the photoelectric processing unit in the present scheme increases the light absorption area to improve the responsivity of the photoelectric signal processing unit, which can realize the miniaturization of the device, thereby facilitating the realization of large-scale integration.

[0145] Specifically, the present application uses full etching or over-etching to etch grooves on the waveguide, thereby increasing the light absorption area (i.e., the cross-sectional area) along the light propagation direction, and further improving the light absorption rate; at the same time, the shape of the light guiding region is limited from both the length direction and the height direction, i.e., the cross-sectional area of the light guiding region gradually increases from the incident end in terms of height and length, which can greatly reduce the reflection of light at the incident end when the light propagates in the light absorption layer (germanium absorption layer) with a larger cross-sectional area, thereby improving the light absorption rate of the photoelectric signal processing unit, i.e., the residual light signal and the output electrical signal in the calculation module can also be "amplified" to a certain extent.

[0146] Further, using the "amplified" residual light signal for error correction analysis can obtain the "amplified" distortion, and thus can also avoid the case where the distortion is too small to be detected.

[0147] Embodiment Six

[0148] The present embodiment provides an optical computing array with self-detection function, comprising a plurality of optical computing modules as described in embodiment five, specifically, the optical computing array comprises:

[0149] A crossbar switch matrix architecture formed by a plurality of rows of input optical waveguides parallel to each other and a plurality of columns of electrical buses parallel to each other; optical input signals are transmitted through the input optical waveguides;

[0150] A plurality of optical splitters arranged at the front end of each intersection node of each row of optical input waveguides and each column of electrical buses;

[0151] A plurality of optoelectronic signal processing units, each corresponding to one of the intersection nodes, and a first input end of the optoelectronic signal processing unit being connected to an output end of the optical splitter through a transmission optical waveguide, and a second input end of the optoelectronic signal processing unit being provided for inputting an external electrical driving signal; an electrical output end of the optoelectronic signal processing unit being connected to the electrical bus in the corresponding intersection node; and a detection unit being connected to an optical output end of the optoelectronic signal processing unit, the detection unit comprising a detector and a data processing unit connected in sequence;

[0152] Wherein, an optical input end of the detector is connected to an electrical output end of the optoelectronic signal processing unit, a first input end of the data processing unit is provided for inputting the electrical driving signal, and a second input end of the data processing unit is connected to an electrical output end of the detector.

[0153] In some embodiments, a third input end of the optoelectronic signal processing unit is further provided for inputting a reference voltage, the reference voltage being used to provide a reference voltage value for the electrical output end, so that the electrical output end can draw a current signal according to the reference voltage value, and the current signal can flow to a designated direction to be collected, thereby realizing summation operation.

[0154] For example, referring to Figure 11 , the reference voltage can be 2V (volts), when the voltage value at the electrical output end is less than 2V, the current signal flows to a first direction a; when the voltage value at the electrical output end is greater than 2V, the current signal flows to a second direction b; wherein, the first direction a and the second direction b are opposite, and the current signals flowing to the same direction are collected at the end of the electrical bus.

[0155] In some embodiments, the optoelectronic signal processing unit comprises: a silicon substrate and an insulating layer deposited on the silicon substrate; the insulating layer is provided with a waveguide layer; the waveguide layer is embedded with a germanium absorption layer; a first depth of the germanium absorption layer embedded in the waveguide layer is less than the thickness of the waveguide layer, or a second depth of the germanium absorption layer embedded in the waveguide layer is equal to the thickness of the waveguide layer;

[0156] A heating unit is arranged at the top and / or bottom of the germanium absorption layer, and the heating unit extends along the length direction of the germanium absorption layer; or,

[0157] The heating unit is arranged on both sides of the germanium absorption layer and extends along the length direction of the germanium absorption layer.

[0158] The heating unit is arranged on both sides of the germanium absorption layer and extends along the length direction of the germanium absorption layer.

[0159] In some embodiments, the germanium absorption layer comprises a light guiding region and a light absorption region arranged in sequence along the light propagation direction,

[0160] The cross-sectional area of the light guiding region gradually increases from the incident end along the direction close to the light absorption region; and the cross-sectional area of the light absorption region is the same along the light propagation direction.

[0161] Embodiment seven

[0162] The embodiment provides a detection method of an optical computing module, referring to Figures 15-17 based on the optical computing module in embodiment five or the optical computing array in embodiment six, comprising the following steps:

[0163] S1, obtaining an electrical driving signal input into the photoelectric signal processing unit and an output electrical signal output by the detector;

[0164] S2, synchronously inputting the electrical driving signal and the output electrical signal into a data processing unit to obtain an electrical signal difference value in a current state;

[0165] S3, repeatedly performing steps S1 and S2 to obtain a plurality of electrical signal difference values;

[0166] S4, calculating a plurality of signal mean values according to the plurality of electrical signal difference values;

[0167] S5, judging whether the signal mean values conform to a preset signal range, if yes, marking the optical computing module as normal, otherwise marking the optical computing module as abnormal.

[0168] The preset signal range is input by a user in advance or obtained in advance according to a large number of experiments and stored in the data processing unit. When the signal mean values do not conform to the preset signal range, it indicates that the signal is distorted, and the optical computing module is marked as abnormal at this time. Artificial judgment is introduced. The abnormality is caused by signal distortion of a signal source, or a problem of a device, or an abnormality caused by other conditions.

[0169] The above detection method can avoid the "misjudgment" problem caused by signal delay by obtaining a plurality of electrical signal difference values through multiple detections respectively and analyzing the plurality of electrical signal difference values.

[0170] In some embodiments, the detection method, based on the optical computing module in embodiment five, or based on the optical computing array in embodiment six, comprises the following steps:

[0171] S1, obtaining an electrical modulation signal S1 input to the optoelectronic signal processing unit, and an output electrical signal I1 output by the detector.

[0172] S2, synchronously inputting the electrical modulation signal S1 and the output electrical signal I1 into a data processing unit, and calculating an electrical signal difference value of the electrical modulation signal S1 and the output electrical signal I1; wherein the difference value has a constant relationship with the current signal O1 output by the optoelectronic signal processing unit, and deviation from the constant can be determined as signal packet loss in the optoelectronic signal processing unit.

[0173] S3, inputting the electrical signal difference value into the data processing unit, and determining whether the electrical signal difference value conforms to a preset difference value range, if yes, marking the optical computing module as normal, otherwise marking the optical computing module as abnormal.

[0174] Referring to Figure 16 , a signal comparison diagram of normal signals and abnormal signals is provided in the figure, wherein the abscissa t is time, and the ordinate P is power.

[0175] It should be noted that in this paper, the term "including", "containing" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or includes elements inherent to such process, method, article or device. Without more limitations, the element defined by the statement "including a" does not exclude the presence of another identical element in the process, method, article or device including the element.

[0176] The embodiments of the present application are described above in combination with the drawings, but the present application is not limited to the above specific embodiments, and the above specific embodiments are only illustrative, not restrictive. Those skilled in the art can make many forms under the inspiration of the present application without departing from the purpose of the present application and the scope protected by the claims, which are all within the protection of the present application.

Claims

1. An optical computing module based on a germanium absorption layer, characterized in that, include: An input optical waveguide and an electrical bus are arranged in a cross configuration. The input end of the input optical waveguide is equipped with a beam splitter. The output end of the beam splitter is connected to the first input end of a photoelectric signal processing unit through a transmission optical waveguide. The electrical output end of the photoelectric signal processing unit is connected to the electrical bus. The photoelectric properties of the light absorption layer in the photoelectric signal processing unit can be changed by writing a control signal to its second input terminal, and the photoelectric signal processing unit can convert the light signal input at the first input terminal into a corresponding current signal and send it to the electrical bus through the electrical output terminal; the photoelectric properties include the light absorption coefficient of the light absorption layer. The product of the multiplier and the multiplicand is encoded in the current signal. The photoelectric signal processing unit includes: a silicon substrate and an insulating layer deposited on the silicon substrate; a waveguide layer is disposed on the insulating layer; and a germanium absorption layer is embedded on the waveguide layer as the light absorption layer.

2. The optical computing module based on a germanium absorption layer according to claim 1, characterized in that, The photoelectric signal processing unit uses pure germanium as the light absorption layer; the germanium absorption layer penetrates the waveguide layer.

3. The optical computing module based on a germanium absorption layer according to claim 2, characterized in that, A heating unit is provided at the top and / or bottom of the germanium absorption layer, and the heating unit extends along the length direction of the germanium absorption layer; or... Heating units are respectively disposed on both sides of the germanium absorption layer, and the heating units extend along the length direction of the germanium absorption layer; or... Heating unit groups are respectively arranged on both sides of the germanium absorption layer, and each heating unit group includes multiple heating units evenly spaced along the length of the germanium absorption layer. The heating levels of two adjacent heating units on the same side are first-level heating and second-level heating, respectively.

4. The optical computing module based on a germanium absorption layer according to claim 2, characterized in that, The germanium absorption layer includes a light guiding region and a light absorbing region arranged sequentially along the light propagation direction. The cross-sectional area of ​​the light guiding region gradually increases from the incident end along the direction close to the light absorption region; the cross-sectional area of ​​the light absorption region is the same along the light propagation direction.

5. The optical computing module based on a germanium absorption layer according to claim 4, characterized in that, When viewed from above, the width of the light guiding region gradually increases from the incident end along the light propagation direction; and when viewed from the side, the width of the light guiding region gradually decreases from the top to the bottom; or, the interface between the light guiding region and the waveguide layer is fan-shaped; and / or, the light absorption region is rectangular when viewed from the side.

6. An optical computing array based on a germanium absorption layer, characterized in that, include: A cross-switch matrix architecture, which is formed by multiple rows of parallel input optical waveguides and multiple columns of parallel electrical buses; The optical input signal is transmitted through the input optical waveguide; Multiple optical splitters are disposed at the front end of the intersection node of each row of optical input waveguides and each column of electrical bus. Multiple photoelectric signal processing units, each photoelectric signal processing unit corresponding to one of the cross nodes, and the first input terminal of the photoelectric signal processing unit is connected to the output terminal of the beam splitter through a transmission optical waveguide, and the electrical output terminal of the photoelectric signal processing unit is connected to the electrical bus in the corresponding cross node; The photoelectric properties of the light absorption layer in the photoelectric signal processing unit can be changed by writing a control signal to its second input terminal, and the photoelectric signal processing unit can convert the light signal input at the first input terminal into a corresponding current signal and send it to the electrical bus through the electrical output terminal; the photoelectric properties include the light absorption coefficient. The product of the multiplier and the multiplicand is encoded in the current signal. The photoelectric signal processing unit includes: a silicon substrate and an insulating layer deposited on the silicon substrate; a waveguide layer is disposed on the insulating layer; and a germanium absorption layer is embedded on the waveguide layer.

7. The optical computing array based on a germanium absorption layer according to claim 6, characterized in that, The photoelectric signal processing unit uses pure germanium as the light absorption layer; the germanium absorption layer penetrates the waveguide layer.

8. The optical computing array based on a germanium absorption layer according to claim 7, characterized in that, A heating unit is provided at the top and / or bottom of the germanium absorption layer, and the heating unit extends along the length direction of the germanium absorption layer; or... Heating units are respectively disposed on both sides of the germanium absorption layer, and the heating units extend along the length direction of the germanium absorption layer; or... Heating unit groups are respectively arranged on both sides of the germanium absorption layer, and each heating unit group includes multiple heating units evenly spaced along the length of the germanium absorption layer. The heating levels of two adjacent heating units on the same side are first-level heating and second-level heating, respectively.

9. The optical computing array based on a germanium absorption layer according to claim 7 or 8, characterized in that, The germanium absorption layer includes a light guiding region and a light absorbing region arranged sequentially along the light propagation direction. The cross-sectional area of ​​the light guiding region gradually increases from the incident end along the direction close to the light absorption region; the cross-sectional area of ​​the light absorption region is the same along the light propagation direction.

10. The optical computing array based on a germanium absorption layer according to claim 7 or 8, characterized in that, Each of the photoelectric signal processing units has a Pad connected to its second input terminal, and a Pad is provided on each column of the electrical bus; and / or, an EOM is provided on each row of input optical waveguides.

Images