Integrated optical chip, preparation method and optical gyroscope

Abstract

The invention discloses an integrated optical chip, a preparation method and an optical gyroscop.The integrated optical chip comprises a substrate and an optical device layer arranged on one side of the substrate, the optical device layer comprises a first coupler, N second couplers and N detectors, the first coupler comprises a first waveguide and N second waveguides connected with the first waveguide, and the N second couplers are connected with the N detectors; the first waveguide is connected with a light source; the N second couplers and the N second waveguides are arranged in a one-to-one correspondence mode, each second coupler comprises a third waveguide and a fourth waveguide, the third waveguides are used for being connected with the interference units, the second waveguides are connected with the third waveguides, and the fourth waveguides are connected with the third waveguides; the N detectors are connected with the N fourth waveguides in a one-to-one correspondence mode, the N detectors are distributed at intervals in at least one of the first direction and the second direction, and the first direction intersects with the second direction.

Description

Technical Field

[0001] The present application belongs to the technical field of optical sensors, and in particular, relates to an integrated optical chip, a preparation method and an optical gyroscope. Background Art

[0002] An optical gyroscope is an optical sensor that detects the angular velocity of a moving carrier and is widely used in aerospace, automation control and other fields. As the core component of an optical gyroscope, an integrated optical chip integrates some active and passive components on a single chip, making the system lighter and more compact compared to traditional discrete components.

[0003] However, there is still much room for improvement in the layout, performance consistency and measurement accuracy of integrated optical chips. Summary of the invention

[0004] The embodiments of the present application provide an integrated optical chip, a preparation method and an optical gyroscope, which can reduce the internal crosstalk of the integrated optical chip and improve the measurement accuracy and stability of the optical gyroscope.

[0005] In a first aspect, an embodiment of the present application provides an integrated optical chip, comprising a substrate and an optical device layer arranged on one side of the substrate, the optical device layer comprising a first coupler, N second couplers and N detectors, the first coupler comprising a first waveguide and N second waveguides connected to the first waveguide, the first waveguide being used to connect a light source; the N second couplers are arranged in a one-to-one correspondence with the N second waveguides, the second coupler comprises a third waveguide and a fourth waveguide, the third waveguide being used to connect an interference unit, the second waveguide being connected to the third waveguide, and the fourth waveguide being connected to the third waveguide; the N detectors are connected in a one-to-one correspondence with the N fourth waveguides, the N detectors are distributed at intervals along at least one of the first direction and the second direction, and the first direction intersects with the second direction; wherein, a light beam enters the first coupler through the first waveguide and is divided into N sub-beams, the sub-beams enter the second coupler through the second waveguide and are then emitted to the interference unit through the third waveguide, and the test light beam transmitted back by the interference unit enters the detector through the third waveguide and the fourth waveguide.

[0006] In some of the embodiments, the optical device layer includes a waveguide cladding and a waveguide core layer, the waveguide cladding is arranged between the substrate and the waveguide core layer, the material of the waveguide cladding includes silicon dioxide, and the material of the waveguide core layer includes at least one of silicon, silicon nitride, gallium arsenide, and indium phosphide.

[0007] In some of the embodiments, the detector includes an active structure and a photoelectric conversion structure arranged along the thickness direction, the active structure is located in the waveguide core layer, the active structure includes a PN junction or a PIN junction, and the photoelectric conversion structure includes at least one of germanium, gold, silver, aluminum, and molybdenum.

[0008] In some of the embodiments, the second waveguide and the fourth waveguide are connected to one side of the second coupler, and the third waveguide is connected to the other side of the second coupler; or,

[0009] In the second coupler, the third waveguide is disposed downstream of the second waveguide, and the fourth waveguide is disposed downstream of the third waveguide.

[0010] In some of the embodiments, the second coupler further includes a fifth waveguide, the fifth waveguide is connected to the second waveguide, the fifth waveguide is connected to an optical parameter meter, and the optical parameter meter is used to measure the wavelength or power of light entering the fifth waveguide from the second waveguide.

[0011] In some of the embodiments, the integrated optical chip also includes a polarization beam splitter for obtaining TE polarized light, and the polarization beam splitter is connected to the first coupler, wherein the polarization beam splitter is connected to the first waveguide, or, there are N polarization beam splitters, the N polarization beam splitters are arranged in a one-to-one correspondence with the N second couplers, and the polarization beam splitter is connected to the second waveguide or the third waveguide.

[0012] In some of the embodiments, the integrated optical chip further comprises a light guide groove, which is connected to the TM output end of the polarization beam splitter; wherein a light absorbing element is provided in the light guide groove, or the output end of the light guide groove is an obliquely polished end face.

[0013] In a second aspect, an embodiment of the present application further provides an optical gyroscope, which includes a light source, N interference units and an integrated optical chip provided by any of the aforementioned embodiments, wherein the light source is connected to the first waveguide, the N interference units are arranged in a one-to-one correspondence with the N third waveguides, the interference unit includes a phase modulator and an interference ring, and the third waveguide is connected to the interference ring through the phase modulator.

[0014] In a third aspect, the present application also provides a method for preparing an integrated optical chip, which is used to prepare the aforementioned integrated optical chip, and the preparation method comprises:

[0015] providing a substrate, and forming a waveguide cladding on one side of the substrate;

[0016] A patterned first dielectric layer is formed on a side of the waveguide cladding away from the substrate, wherein the first dielectric layer includes a first waveguide, a first coupler, N second waveguides, N fourth waveguides, N second couplers and N third waveguides;

[0017] N detectors are formed on a side of the first dielectric layer away from the waveguide cladding, and the detectors are connected to the fourth waveguide.

[0018] In some embodiments, the step of forming N detectors on a side of the first dielectric layer away from the waveguide cladding comprises:

[0019] A first shielding portion is provided above the first dielectric layer, and the first dielectric layer is doped to form an active structure;

[0020] A second dielectric layer is formed above the first dielectric layer, and a photoelectric conversion structure is formed in the second dielectric layer, wherein the photoelectric conversion structure is arranged in contact with the active structure;

[0021] A protective layer is formed on the second dielectric layer, a third shielding portion is arranged on the protective layer, the protective layer is etched to obtain a contact hole, a conductive structure is formed in the contact hole, and the conductive structure is electrically connected to at least part of the photoelectric conversion structure.

[0022] The integrated optical chip of the embodiment of the present application is split by the first coupler so that the integrated optical chip can realize angular velocity measurement in at least two directions, which helps to improve the measurement consistency between different axes. The light beam output by the first coupler enters the interference unit via the second waveguide and the third waveguide, and enters the detector through the third waveguide and the fourth waveguide after interference, and is converted into an electrical signal by the detector to output the measurement result. The present application also adjusts the distribution relationship of multiple detectors in the chip, improves the layout, improves the integration of the optical chip, and reduces the crosstalk that may occur between the detectors, thereby achieving an improvement in the measurement accuracy of the optical gyroscope. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Moreover, the same reference numerals are used throughout the drawings to represent the same components. In the drawings:

[0024] Figure 1 A schematic diagram of the structure of an integrated optical chip according to some embodiments of the present application;

[0025] Figure 2 for Figure 1 A schematic cross-sectional view of the integrated optical chip shown;

[0026] Figure 3 A schematic diagram of the structure of an integrated optical chip according to some embodiments of the present application;

[0027] Figure 4 A schematic diagram of the structure of an optical gyroscope according to some embodiments of the present application;

[0028] Figures 5a-5f A schematic diagram of the process of preparing an integrated optical chip according to some embodiments of the present application.

[0029] The reference numerals in the specific implementation manner are as follows:

[0030] 01. Substrate; 02. Waveguide cladding; 03. Waveguide core;

[0031] 110, first waveguide; 120, second waveguide; 130, third waveguide; 140, fourth waveguide;

[0032] 210, a first coupler; 220, a second coupler; 230, a polarization beam splitter;

[0033] 300, detector; 310, active structure; 320, photoelectric conversion structure; 330, conductive structure;

[0034] 410, light source; 420, interference unit; 421, phase modulator; 422, interference ring. DETAILED DESCRIPTION

[0035] The following embodiments of the technical solution of the present application are described in detail in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0036] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" in the specification and claims of this application and the above-mentioned figure descriptions and any variations thereof are intended to cover non-exclusive inclusions.

[0037] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise clearly and specifically defined.

[0038] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0039] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0040] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0041] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0042] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0043] In order to solve the problems of the prior art, the embodiments of the present application provide an integrated optical chip, a preparation method and an optical gyroscope. The integrated optical chip provided by the embodiments of the present application is first introduced below.

[0044] First, see Figures 1 to 3 An embodiment of the present application provides an integrated optical chip, including a substrate 01 and an optical device layer arranged on one side of the substrate 01, the optical device layer including a first coupler 210, N second couplers 220 and N detectors 300, the first coupler 210 including a first waveguide 110 and N second waveguides 120 connected to the first waveguide 110, the first waveguide 110 is used to connect to a light source 410; the N second couplers 220 are arranged in a one-to-one correspondence with the N second waveguides 120, the second coupler 220 includes a third waveguide 130 and a fourth waveguide 140, the third waveguide 130 is used to connect to an interference unit 420, the second waveguide 120 is connected to the third waveguide 130, and the fourth waveguide 140 is connected to the third waveguide 130; the N detectors 300 are connected to the N fourth waveguides 140 in a one-to-one correspondence.

[0045] See also Figure 4The light beam emitted by the light source 410 enters the first coupler 210 through the first waveguide 110 and is divided into N sub-beams. The sub-beams enter the second coupler 220 through the second waveguide 120 and are emitted to the interference unit 420 through the third waveguide 130. The test light beam transmitted back by the interference unit 420 enters the detector 300 through the third waveguide 130 and the fourth waveguide 140. The detector 300 converts the optical signal into an electrical signal for output, so as to measure the deflection angle of the interference unit 420.

[0046] It is understood that N is 2 or 3.

[0047] Thus, the integrated optical chip performs light splitting through the first coupler 210, so that the integrated optical chip can achieve angular velocity measurement in at least two directions, which helps to improve the measurement consistency between different axes.

[0048] Wherein, along at least one of the first direction and the second direction, the N detectors 300 are distributed at intervals, and the first direction intersects the second direction.

[0049] Optionally, the first direction is perpendicular to the second direction.

[0050] Further optionally, the N detectors 300 are distributed in a stepped manner, that is, when N is 3, along the first direction or the second direction, one of the detectors 300 is located between the other two detectors 300 .

[0051] Therefore, while the detector 300 is set in the optical device layer to improve the integration of the optical chip, on the one hand, the chip area is reduced through the reasonable layout of the detector 300, which is conducive to the lightweight and miniaturization of the optical gyroscope product; on the other hand, the crosstalk that may occur between the detectors 300 is reduced, thereby achieving an improvement in the measurement accuracy of the optical gyroscope.

[0052] According to some embodiments of the present application, the integrated optical chip further includes a polarization beam splitter 230 , which is disposed in the optical device layer and upstream of the interference unit 420 , and is used to obtain TE polarized light that can produce a Segnac effect in the interference unit 420 .

[0053] Optionally, the polarization beam splitter 230 is connected to the first coupler 210. Exemplarily, the first waveguide 110 is connected to an output end of the polarization beam splitter 230.

[0054] Optionally, N polarization beam splitters 230 are provided, and the N polarizers are connected to the N second couplers 220 in a one-to-one correspondence. Exemplarily, the polarization beam splitter 230 is connected to the second waveguide 120 , or the polarization beam splitter 230 is connected to the third waveguide 130 .

[0055] Optionally, the polarization beam splitter 230 may include at least one of an asymmetric directional coupler structure, a symmetric directional coupler, a multi-mode interferometer, a Mach-Zehnder interferometer, a photonic crystal polarizer, and a grating waveguide polarizer.

[0056] Therefore, the polarization beam splitter 230 is integrated inside the optical chip, which improves the chip integration and contributes to the lightweight and miniaturization of the optical gyroscope product.

[0057] It is understandable that in some other embodiments, the integrated optical chip does not have a polarization beam splitter 230 to reduce the difficulty of processing, and the light beam passes through a polarization beam splitter or other structures before entering the first waveguide 110 to obtain TE polarized light.

[0058] It should be noted that in optical waveguides, TE polarized light usually has better transmission characteristics, including lower loss and higher mode stability. The square distribution and waveguide conditions of TE polarized light are more suitable for long-distance transmission and high-precision measurement, which is crucial for the accuracy and stability of optical gyroscopes. In actual operation, TE polarized light is relatively easy to control and keep stable. Optical gyroscopes require precise optical path and phase control, and TE polarized light provides a more stable polarization state, which helps to improve the stability and repeatability of measurements.

[0059] According to some embodiments of the present application, the integrated optical chip further includes a light-introducing groove, which is disposed in the waveguide core layer and connected to the TM output end of the polarization beam splitter.

[0060] Optionally, in some embodiments, a light absorbing member is provided in the light guiding groove, and the light guiding groove can absorb the TM polarized light separated from the polarization beam splitter 230. Exemplarily, the light absorbing member can be but is not limited to black epoxy resin glue, carbon black filled glue or nano material light absorbing glue.

[0061] Optionally, in some other embodiments, the light guiding groove is bent, and the TM polarized light is reflected multiple times in the light guiding groove and finally emitted from the end face of the integrated optical chip. Exemplarily, the emission end of the light guiding groove is an obliquely polished end face, and the angle of the obliquely polished end face is 7° to 15°.

[0062] Therefore, the light-guiding groove can guide the exit path of the TM polarized light output by the polarization beam splitter, thereby reducing the TM polarized light entering the interference unit 420 and reducing the crosstalk of the TM polarized light to the subsequent interference unit 420, which helps to improve the measurement accuracy of the optical gyroscope.

[0063] According to some embodiments of the present application, the second waveguide 120 and the third waveguide 130 are disposed on two sides of the second coupler 220 .

[0064] Optionally, the second coupler 220 is a 1×2 coupler, the second waveguide 120 and the fourth waveguide 140 are arranged on the same side, and the third waveguide 130 is arranged on the other side.

[0065] Optionally, the second coupler 220 is a circulator, the third waveguide 130 is disposed downstream of the second waveguide 120 , and the fourth waveguide 140 is disposed downstream of the third waveguide 130 .

[0066] Therefore, the distance between the detector 300 and the interference unit 420 is extended without expanding the area of ​​the integrated optical chip, reducing the internal crosstalk of the integrated optical chip, which helps to improve the accuracy of the optical gyroscope.

[0067] According to some embodiments of the present application, the second coupler 220 further includes a fifth waveguide, the fifth waveguide is connected to the second waveguide 120, and the third waveguide 130 is connected to an optical parameter meter.

[0068] Optionally, the second coupler 220 is a 2x2 coupler, the second waveguide 120 and the fourth waveguide 140 are arranged on the same side, and the third waveguide 130 and the fifth waveguide are arranged on the other side.

[0069] Optionally, the second coupler 220 is a circulator, the fifth waveguide is arranged downstream of the second waveguide 120, and the third waveguide 130 is arranged downstream of the fifth waveguide.

[0070] Therefore, the power or wavelength of the sub-beam output by the second waveguide 120 is measured by the optical parameter meter, which can be used as a reference for the test beam to improve the detection accuracy of the optical gyroscope product.

[0071] According to some embodiments of the present application, the optical device layer includes a waveguide cladding 02 and a waveguide core 03 . The waveguide cladding 02 is disposed between the substrate 01 and the waveguide core 03 . The refractive index of the waveguide cladding 02 is lower than that of the waveguide core 03 .

[0072] Optionally, the material of the waveguide cladding 02 includes silicon dioxide.

[0073] Optionally, the material of the waveguide core layer 03 includes at least one of silicon, silicon nitride, gallium arsenide, and indium phosphide.

[0074] Therefore, setting the waveguide cladding 02 above the substrate 01 helps to flatten the processing plane of the waveguide core layer 03 and improve the preparation quality of the optical device of the waveguide core layer 03; at the same time, it reduces the dissipation of light propagating in the waveguide core layer 03 and improves the optical performance of the integrated optical chip.

[0075] According to some embodiments of the present application, the detector 300 includes an active structure 310 and a photoelectric conversion structure 320 arranged along the thickness direction, and the active structure 310 is located in the waveguide core layer 03 .

[0076] Optionally, the photoelectric conversion structure 320 includes at least one of germanium, gold, silver, aluminum, and molybdenum. Exemplarily, the photoelectric conversion structure 320 is made of germanium material.

[0077] Optionally, the active structure 310 includes a PN junction or a PIN junction.

[0078] It is understandable that the detector 300 further includes a contact electrode exposed to the photoelectric device layer to achieve interconnection between the detector 300 and other electrical devices.

[0079] Taking the silicon-germanium heterostructure as an example, when the test light beam enters the active structure 310, since the energy of the photon is greater than the bandgap width of the silicon-germanium alloy, the photon can be absorbed by the material and excite the electron transition in the valence band to form an electron-hole pair. The electron-hole pair can form a photocurrent in the active structure 310, which is then detected and amplified by an external electrical device through the contact electrode and converted into an electrical signal output, thereby achieving the purpose of measuring the angular velocity of the moving carrier through optical interference.

[0080] Second, see Figure 4 The embodiment of the present application provides an optical gyroscope, which includes a light source 410, N interference units 420, and an integrated optical chip provided by any of the above embodiments, wherein the interference unit 420 includes a phase modulator 421 and an interference ring 422, and the interference unit 420 is connected to the light source 410 through the integrated optical chip. Among them, the first waveguide 110 is connected to the light source 410, and the N third waveguides 130 are connected to the N phase modulators 421 in a one-to-one correspondence. The optical gyroscope has all the beneficial effects of the above integrated optical chip.

[0081] Optionally, the interference ring 422 is configured as a fiber ring, or other annular structures capable of causing the light beam to undergo a Segnac effect therein.

[0082] Optionally, the light source 410 is configured as a light source 410 chip, or other carriers mounted with the light source 410 , so as to be fixed relative to the integrated optical chip, thereby achieving the purpose of introducing a light beam into the integrated optical chip.

[0083] Further optionally, the light source 410 is connected to the integrated optical chip by termination.

[0084] According to certain embodiments of the present application, the optical gyroscope also includes a circuit board, and the N detectors 300 are interconnected with the circuit board to receive electrical signals transmitted by the detectors 300 and output detection results, thereby improving the integration level of the optical gyroscope and contributing to lightweight and miniaturization of the product.

[0085] Optionally, the circuit board is disposed on one side of the integrated optical chip along the first direction, and the light source 410 and the interference unit 420 are disposed on two ends of the integrated optical chip along the second direction.

[0086] Third, see Figures 5a-5f The present application also provides a method for preparing an integrated optical chip, comprising:

[0087] S100, providing a substrate 01, and forming a waveguide cladding 02 on one side of the substrate 01;

[0088] S200, forming a patterned first dielectric layer on a side of the waveguide cladding 02 facing away from the substrate 01, the first dielectric layer comprising a first waveguide 110, a first coupler 210, N second waveguides 120, N fourth waveguides 140, N second couplers 220 and N third waveguides 130;

[0089] S300 , forming N detectors 300 on a side of the first dielectric layer away from the waveguide cladding 02 , and the detectors 300 are connected to the fourth waveguide 140 .

[0090] According to some embodiments of the present application, step S100 includes:

[0091] S110, providing a substrate 01, and pre-processing one side of the substrate 01 to obtain a preset track;

[0092] S130 , preparing a waveguide cladding 02 on the side of the substrate 01 where a preset track is formed.

[0093] Optionally, in step S110, the pretreatment process is wet etching, and the etching solution includes hydrofluoric acid and nitric acid.

[0094] Optionally, in step S130, the material of the waveguide cladding 02 is silicon dioxide, and the waveguide cladding 02 is prepared by physical vapor deposition or chemical vapor deposition.

[0095] According to some embodiments of the present application, in step S200 , the material of the first dielectric layer is silicon, and the impurity concentration of the first dielectric layer is low to reduce light loss.

[0096] Optionally, in step S200 , the first dielectric layer is prepared by oxide chemical vapor deposition.

[0097] According to some embodiments of the present application, step S300 includes:

[0098] S310, disposing a first shielding portion above the first dielectric layer, and doping the first dielectric layer to form an active structure 310;

[0099] S320, forming a second dielectric layer above the first dielectric layer, and forming a photoelectric conversion structure 320 on the second dielectric layer, wherein the photoelectric conversion structure 320 is disposed in contact with the active structure 310;

[0100] S330 , forming a protective layer on the second dielectric layer, disposing a third shielding portion on the protective layer, etching the protective layer to obtain a contact hole, forming a conductive structure 330 in the contact hole, and the conductive structure 330 is electrically connected to at least a portion of the photoelectric conversion structure 320 .

[0101] It is understandable that the protective layer at least covers the photoelectric conversion structure 320 and the first dielectric layer. Exemplarily, the protective layer covers the second dielectric layer.

[0102] According to some embodiments of the present application, in step S310, before doping begins, the first dielectric layer is pretreated, and the pretreatment includes at least one of cleaning, removing surface impurities, and pre-soaking.

[0103] Optionally, in step S310, source and drain dopants are implanted in a first temperature environment, and the first temperature environment is 1000°C to 1100°C.

[0104] Optionally, in step S310, after the source and drain dopants are implanted, a diffusion annealing process is performed in a second temperature environment, wherein the second temperature environment is 1000°C to 1100°C.

[0105] According to some embodiments of the present application, step S320 includes:

[0106] S321, forming a second dielectric layer above the first dielectric layer, disposing a second shielding portion above the second dielectric layer, and etching the second dielectric layer to obtain a process window to expose the first dielectric layer;

[0107] S322, depositing a germanium film within the process window to form a silicon-germanium heterostructure;

[0108] S323, providing a third temperature environment to allow the germanium film to grow germanium crystals within the process window.

[0109] Optionally, in step S322 , a silicon-germanium heterostructure is formed by chemically reacting the germanium film with the silicon material of the first dielectric layer.

[0110] Optionally, in step S323, a third temperature environment is provided by a titanium nitride heating electrode, and the growth rate and crystal quality of the germanium crystal are adjusted by controlling the temperature of the heating electrode.

[0111] According to some embodiments of the present application, in step S330 , a tungsten material and a gold electrode are filled in the contact hole to form a conductive structure 330 .

[0112] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be included in the scope of the claims and specification of the present application. In particular, as long as there is no structural conflict, the various technical features mentioned in the various embodiments can be combined in any way. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. An integrated optical chip, characterized in that: The invention comprises a substrate and an optical device layer arranged on one side of the substrate, wherein the optical device layer comprises: A first coupler comprises a first waveguide and N second waveguides connected to the first waveguide, wherein the first waveguide is used to connect to a light source; N second couplers are arranged in one-to-one correspondence with the N second waveguides, the second coupler includes a third waveguide and a fourth waveguide, the third waveguide is used to connect the interference unit, the second waveguide is connected to the third waveguide, and the fourth waveguide is connected to the third waveguide; N detectors are connected to the N fourth waveguides in a one-to-one correspondence, and the N detectors are spaced apart along at least one of a first direction and a second direction, and the first direction intersects the second direction; The light beam enters the first coupler through the first waveguide and is divided into N sub-beams. The sub-beams enter the second coupler through the second waveguide and are then emitted to the interference unit through the third waveguide. The test light beam transmitted back by the interference unit enters the detector through the third waveguide and the fourth waveguide.

2. The integrated optical chip according to claim 1, characterized in that: The optical device layer includes a waveguide cladding and a waveguide core layer, wherein the waveguide cladding is disposed between the substrate and the waveguide core layer, a material of the waveguide cladding includes silicon dioxide, and a material of the waveguide core layer includes at least one of silicon, silicon nitride, gallium arsenide, and indium phosphide.

3. The integrated optical chip according to claim 2, characterized in that: The detector includes an active structure and a photoelectric conversion structure arranged along the thickness direction, the active structure is located in the waveguide core layer, the active structure includes a PN junction or a PIN junction, and the photoelectric conversion structure includes at least one of germanium, gold, silver, aluminum, and molybdenum.

4. The integrated optical chip according to claim 1, characterized in that: The second waveguide and the fourth waveguide are connected to one side of the second coupler, and the third waveguide is connected to the other side of the second coupler; or, In the second coupler, the third waveguide is disposed downstream of the second waveguide, and the fourth waveguide is disposed downstream of the third waveguide.

5. The integrated optical chip according to claim 4, characterized in that: The second coupler further includes a fifth waveguide connected to the second waveguide, and an optical parameter meter is connected to the fifth waveguide, and the optical parameter meter is used to measure the wavelength or power of light entering the fifth waveguide from the second waveguide.

6. The integrated optical chip according to claim 1, characterized in that: The integrated optical chip also includes a polarization beam splitter for obtaining TE polarized light, and the polarization beam splitter is connected to the first coupler, wherein the polarization beam splitter is connected to the first waveguide, or the polarization beam splitter is provided with N polarization beam splitters, the N polarization beam splitters are arranged in a one-to-one correspondence with the N second couplers, and the polarization beam splitter is connected to the second waveguide or the third waveguide.

7. The integrated optical chip according to claim 6, characterized in that: The integrated optical chip further comprises a light-guiding groove, which is connected to the TM output end of the polarization beam splitter; wherein a light-absorbing member is arranged in the light-guiding groove, or the output end of the light-guiding groove is an obliquely polished end face.

8. An optical gyroscope, characterized in that: include: light source; The integrated optical chip according to any one of claims 1 to 7, wherein the light source is connected to the first waveguide, N interference units are arranged in one-to-one correspondence with the N third waveguides. The interference unit includes a phase modulator and an interference ring. The third waveguide is connected to the interference ring through the phase modulator.

9. A method for preparing an integrated optical chip, for preparing the integrated optical chip according to any one of claims 1 to 7, characterized in that: include: providing a substrate, and forming a waveguide cladding on one side of the substrate; A patterned first dielectric layer is formed on a side of the waveguide cladding away from the substrate, wherein the first dielectric layer includes a first waveguide, a first coupler, N second waveguides, N fourth waveguides, N second couplers and N third waveguides; N detectors are formed on a side of the first dielectric layer away from the waveguide cladding, and the detectors are connected to the fourth waveguide.

10. The method for preparing an integrated optical chip according to claim 9, characterized in that: The step of forming N detectors on the side of the first dielectric layer away from the waveguide cladding comprises: A first shielding portion is provided above the first dielectric layer, and the first dielectric layer is doped to form an active structure; A second dielectric layer is formed above the first dielectric layer, and a photoelectric conversion structure is formed in the second dielectric layer, wherein the photoelectric conversion structure is arranged in contact with the active structure; A protective layer is formed on the second dielectric layer, a third shielding portion is arranged on the protective layer, the protective layer is etched to obtain a contact hole, a conductive structure is formed in the contact hole, and the conductive structure is electrically connected to at least part of the photoelectric conversion structure.

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