CN111446309B - Waveguide integrated photoelectric detector and manufacturing method thereof - Google Patents

Waveguide integrated photoelectric detector and manufacturing method thereof Download PDF

Info

Publication number
CN111446309B
CN111446309B CN202010206294.9A CN202010206294A CN111446309B CN 111446309 B CN111446309 B CN 111446309B CN 202010206294 A CN202010206294 A CN 202010206294A CN 111446309 B CN111446309 B CN 111446309B
Authority
CN
China
Prior art keywords
substrate
photoelectric conversion
optical waveguide
waveguide
guide
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202010206294.9A
Other languages
Chinese (zh)
Other versions
CN111446309A (en
Inventor
熊文娟
亨利·H·阿达姆松
王桂磊
张玄
唐兴权
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Institute of Microelectronics of CAS
Original Assignee
Institute of Microelectronics of CAS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Institute of Microelectronics of CAS filed Critical Institute of Microelectronics of CAS
Priority to CN202010206294.9A priority Critical patent/CN111446309B/en
Publication of CN111446309A publication Critical patent/CN111446309A/en
Application granted granted Critical
Publication of CN111446309B publication Critical patent/CN111446309B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/08—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof in which radiation controls flow of current through the device, e.g. photoresistors
    • H01L31/10—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof in which radiation controls flow of current through the device, e.g. photoresistors characterised by potential barriers, e.g. phototransistors
    • H01L31/101—Devices sensitive to infrared, visible or ultraviolet radiation
    • H01L31/102—Devices sensitive to infrared, visible or ultraviolet radiation characterised by only one potential barrier
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
    • G02B6/12—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
    • G02B6/12004—Combinations of two or more optical elements
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
    • G02B6/12—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
    • G02B6/122—Basic optical elements, e.g. light-guiding paths
    • G02B6/124—Geodesic lenses or integrated gratings
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
    • G02B6/12—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
    • G02B6/122—Basic optical elements, e.g. light-guiding paths
    • G02B6/125—Bends, branchings or intersections
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/02—Details
    • H01L31/0232—Optical elements or arrangements associated with the device
    • H01L31/02325—Optical elements or arrangements associated with the device the optical elements not being integrated nor being directly associated with the device
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/18—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof
    • H01L31/1804—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof comprising only elements of Group IV of the Periodic Table
    • H01L31/1808—Processes or apparatus specially adapted for the manufacture or treatment of these devices or of parts thereof comprising only elements of Group IV of the Periodic Table including only Ge
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
    • G02B6/12—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
    • G02B2006/12035—Materials
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/10—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type
    • G02B6/12—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings of the optical waveguide type of the integrated circuit kind
    • G02B2006/12133—Functions
    • G02B2006/12138—Sensor
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Condensed Matter Physics & Semiconductors (AREA)
  • Electromagnetism (AREA)
  • Computer Hardware Design (AREA)
  • Power Engineering (AREA)
  • Optics & Photonics (AREA)
  • Manufacturing & Machinery (AREA)
  • Light Receiving Elements (AREA)
  • Optical Integrated Circuits (AREA)

Abstract

The invention discloses a waveguide integrated photoelectric detector and a manufacturing method thereof, and relates to the technical field of photoelectricity. The waveguide integrated type photodetector includes a substrate, at least one optical waveguide, and a photoelectric conversion structure. An optical waveguide is formed over the substrate. Each optical waveguide includes a guiding portion. The guide part is provided with a plurality of guide structures, at least two of the guide structures are distributed along the thickness direction of the substrate, and the orthographic projection edges of the adjacent two guide structures on the substrate are jointed. The photoelectric conversion structure is formed above the optical waveguide facing away from the substrate. The guide part in the waveguide integrated photoelectric detector provided by the invention comprises a plurality of guide structures distributed in a step shape. The plurality of guide structures can transmit and guide light rays, so that the light rays can be guided into the photoelectric conversion structure to complete the photoelectric conversion process, integration of the optical waveguide formed by the waveguide material and the photoelectric conversion structure is realized, and the monolithic integration degree of the waveguide integrated photoelectric detector is improved.

Description

Waveguide integrated photoelectric detector and manufacturing method thereof
Technical Field
The invention relates to the technical field of photoelectricity, in particular to a waveguide integrated photoelectric detector and a manufacturing method thereof.
Background
A photodetector is a device that converts light intensity into an electrical signal. The method has the advantages of high resolution, high response speed and low manufacturing cost. Therefore, photodetectors are widely used in optical communication systems ranging from remote control to fiber-optic communication.
At present, the mainstream waveguide integrated photoelectric detector in the industry is formed by monolithic integration of a Si-based optical waveguide and a Ge-based detector which are established on an SOI platform. However, the Si-based optical waveguide in the conventional waveguide integrated photodetector has high optical loss and a relatively narrow light transmission range, and thus, a waveguide material having better performance is urgently developed.
It is expected that if monolithic integration of an optical waveguide (e.g., a third generation silicon nitride optical waveguide) with a Ge-based detector having superior performance can be achieved, the operating performance of the waveguide-integrated photodetector can be improved, and the manufacturing cost of the waveguide-integrated photodetector can be reduced. However, due to material and structure limitations, it is difficult to integrate Ge-based detectors on optical waveguides with superior performance (e.g., third generation silicon nitride optical waveguides).
Disclosure of Invention
The invention aims to provide a waveguide integrated photoelectric detector and a manufacturing method thereof, so as to realize integration of a waveguide material and a photoelectric conversion structure and improve the monolithic integration and the working performance of the waveguide integrated photoelectric detector.
In order to achieve the above object, the present invention provides a waveguide integrated type photodetector. The waveguide integrated type photodetector includes:
a substrate;
the optical waveguide structure comprises at least one optical waveguide, at least one optical waveguide is formed above a substrate, each optical waveguide comprises a guide part, each guide part is provided with a plurality of guide structures, at least two of the guide structures are distributed along the thickness direction of the substrate, the orthographic projection edges of the adjacent two guide structures on the substrate are jointed, and the at least one optical waveguide is made of waveguide materials;
the photoelectric conversion structure is formed above the at least one optical waveguide, and the guide portion is used for guiding light into the photoelectric conversion structure.
In the waveguide-integrated photodetector provided by the present invention, each optical waveguide includes a guide portion having a plurality of guide structures, and at least two of the guide structures are distributed along the thickness direction of the substrate. In other words, the plurality of guide structures are distributed over the substrate in a step shape and are distributed along a direction gradually approaching the photoelectric conversion structure. The plurality of guide structures can sequentially transmit and guide light rays, so that the light rays can be guided into the photoelectric conversion structure through the guide structure closest to the photoelectric conversion structure, and the photoelectric conversion process is completed. On the basis, the optical waveguide comprising the plurality of guide structures is an optical waveguide formed by waveguide materials, wherein the waveguide materials comprise any waveguide materials which can be used for forming the optical waveguide, so that integration of a plurality of optical waveguides and the photoelectric conversion structure can be realized, and the monolithic integration degree of the waveguide integrated type photoelectric detector can be improved.
Further, the guiding portion comprises a first guiding structure, a second guiding structure and a third guiding structure for connection, wherein,
the surface of the first guide structure, which faces away from the substrate, and the surface of the third guide structure, which faces away from the substrate, form an included angle of 90-170 degrees;
the surface of the second guide structure facing away from the substrate forms an angle of 90 DEG to 170 DEG with the surface of the third guide structure facing away from the substrate.
Furthermore, at least one optical waveguide is made of an amorphous waveguide material, and the amorphous waveguide material comprises silicon nitride;
the photoelectric conversion structure is made of a photoelectric material.
Further, each optical waveguide further comprises a grating part; the grating part is used for diffracting the light rays, so that the diffracted light rays are coupled to the guide part.
Further, the waveguide integrated type photodetector further includes: the photoelectric conversion structure is formed on the surface of the light-transmitting structure, which is far away from the substrate.
Further, the waveguide integrated photodetector further includes a light-transmissive bonding layer, and the bonding layer is located between the photoelectric conversion structure and the at least one optical waveguide.
The invention also provides a manufacturing method of the waveguide integrated photoelectric detector, which comprises the following steps:
providing a first substrate;
forming at least one optical waveguide above the first substrate, wherein each optical waveguide comprises a guide part, the guide part is provided with a plurality of guide structures, at least two of the guide structures are distributed along the thickness direction of the first substrate, the orthographic projection edges of two adjacent guide structures on the first substrate are jointed, and at least one optical waveguide is made of waveguide materials;
and a photoelectric conversion structure is formed above the at least one optical waveguide, which is far away from the first substrate, and the guide part is used for guiding light into the photoelectric conversion structure.
Compared with the prior art, the manufacturing method of the waveguide integrated type photoelectric detector provided by the invention has the same beneficial effects as the semiconductor device provided by the technical scheme, and the details are not repeated herein.
Further, the guiding portion comprises a first guiding structure, a second guiding structure and a third guiding structure for connection, wherein,
the surface of the first guide structure departing from the first substrate and the surface of the third guide structure departing from the first substrate form an included angle of 90-170 degrees;
the surface of the second guide structure facing away from the first substrate forms an angle of 90 DEG to 170 DEG with the surface of the third guide structure facing away from the first substrate.
Furthermore, at least one optical waveguide is made of an amorphous waveguide material, and the amorphous waveguide material comprises silicon nitride;
the photoelectric conversion structure is made of a photoelectric material.
Further, each optical waveguide further comprises a grating part; the grating part is used for diffracting the light rays, so that the diffracted light rays are coupled to the guide part.
Further, after providing the first substrate, before forming at least one optical waveguide over the first substrate, the method for manufacturing the waveguide-integrated photodetector further includes:
forming a first light-transmitting layer over a surface of a first substrate;
after forming the at least one optical waveguide above the first substrate, and before forming the photoelectric conversion structure above the at least one optical waveguide away from the first substrate, the method for manufacturing the waveguide-integrated photodetector further includes:
and forming a second light-transmitting layer covering the at least one optical waveguide on the surface of the at least one optical waveguide, which is far away from the first substrate, wherein the first light-transmitting layer and the second light-transmitting layer form a light-transmitting structure.
Further, after forming at least one optical waveguide above the first substrate, before forming the photoelectric conversion structure above the at least one optical waveguide away from the first substrate, the method for manufacturing the waveguide integrated type photodetector further includes:
providing a substrate; the substrate comprises a second substrate and a photoelectric conversion structure formed on the second substrate;
bonding a photoelectric conversion structure included in a substrate and at least one optical waveguide together to obtain a pre-integrated structure;
and removing the second substrate included in the pre-integrated structure.
Further, the substrate further comprises a buffer layer located between the second substrate and the photoelectric conversion structure;
after removing the second substrate included in the pre-integrated structure, and before forming the photoelectric conversion structure above the at least one optical waveguide deviating from the first substrate, the method for manufacturing the waveguide integrated type photodetector further includes:
the buffer layer included in the pre-integrated structure is removed.
Further, the substrate further comprises a light-transmitting bonding layer, and the bonding layer is located between the photoelectric conversion structure and the at least one optical waveguide;
bonding together a photoelectric conversion structure comprised by a substrate and at least one optical waveguide, obtaining a pre-integrated structure comprising:
and bonding the bonding layer included by the substrate and the at least one optical waveguide together to obtain the pre-integrated structure.
Drawings
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. In the drawings:
FIG. 1 is a schematic structural diagram of a waveguide integrated photodetector according to an embodiment of the present invention;
FIG. 2 is a schematic diagram illustrating the transmission direction of light in an optical waveguide according to an embodiment of the present invention;
FIG. 3 is a schematic diagram illustrating a structure after a first substrate is provided in an embodiment of the invention;
fig. 4 is a schematic diagram illustrating a structure after a first transparent layer is formed according to an embodiment of the disclosure;
FIG. 5 is a schematic diagram of a structure after forming an optical waveguide according to an embodiment of the present invention;
FIG. 6 is a schematic structural diagram illustrating a structure of a light-transmitting material covering an optical waveguide according to an embodiment of the present invention;
fig. 7 is a schematic diagram illustrating a structure after a second light-transmitting layer is formed according to an embodiment of the invention;
FIG. 8 is a schematic view of a structure after a second substrate is provided in an embodiment of the present invention;
FIG. 9 is a schematic diagram illustrating a structure after forming a buffer layer according to an embodiment of the present invention;
FIG. 10 is a schematic view of a structure after a first electrode forming layer is formed according to an embodiment of the present invention;
FIG. 11 is a diagram illustrating a structure of a bonding layer formed according to an embodiment of the present invention;
fig. 12 is a schematic structural view illustrating bonding of a photoelectric conversion structure included in a substrate and an optical waveguide according to an embodiment of the present invention;
FIG. 13 is a schematic diagram of a bonded structure according to an embodiment of the present invention;
FIG. 14 is a schematic view of the structure after the second substrate and the buffer layer are removed in the embodiment of the present invention;
FIG. 15 is a schematic structural diagram of a photoelectric conversion layer and a second electrode layer after being formed in an embodiment of the invention;
FIG. 16 is a schematic structural diagram of a waveguide integrated photodetector according to an embodiment of the present invention;
fig. 17 is a flowchart of a method for manufacturing a waveguide integrated photodetector according to an embodiment of the present invention.
Reference numerals:
the optical waveguide device comprises a first substrate 1, an optical waveguide 2, a photoelectric conversion structure 3, a grating portion 4, a guide portion 5, a first guide structure 6, a second guide structure 7, a third guide structure 8, a light-transmitting structure 9, a first light-transmitting layer 10, a second light-transmitting layer 11, a substrate 12, a second substrate 13, a preformed structure 14, a first electrode forming layer 15, a photoelectric conversion forming layer 16, a second electrode forming layer 17, a pre-integrated structure 18, a buffer layer 19, a bonding layer 20, a first electrode layer 21, a photoelectric conversion layer 22, a second electrode layer 23, an isolation layer 24, a first wiring terminal 25 and a second wiring terminal 26.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
A photodetector is a device that can convert light intensity into an electrical signal. The method has the advantages of high resolution, high response speed and low manufacturing cost. Therefore, photodetectors are widely used in optical communication systems ranging from remote control to fiber-optic communication.
At present, the mainstream waveguide integrated photoelectric detector in the industry is formed by monolithic integration of a Si-based optical waveguide and a Ge-based detector which are established on an SOI platform. However, since Si has a small refractive index, an optical waveguide made of Si material has a high transmission loss during light transmission. In addition, the Si-based optical waveguide has a relatively narrow light transmission range, so that the performance of the waveguide integrated photodetector is poor.
It is expected that if monolithic integration of an optical waveguide (e.g., a third generation silicon nitride optical waveguide) with a Ge-based detector having superior performance can be achieved, the operating performance of the waveguide-integrated photodetector can be improved, and the manufacturing cost of the waveguide-integrated photodetector can be reduced. However, due to the limitation of materials and structures, it is difficult to integrate Ge-based detectors on optical waveguides with superior performance (e.g., third generation silicon nitride optical waveguides), so that the monolithic integration of waveguide-integrated photodetectors is low.
In order to solve the technical problem that a Ge-based detector is difficult to integrate on an optical waveguide with excellent performance, so that the monolithic integration degree of a waveguide integrated photoelectric detector is low, the embodiment of the invention provides a waveguide integrated photoelectric detector and a manufacturing method thereof. The waveguide integrated type photoelectric detector comprises an optical waveguide with a plurality of guide structures. And a plurality of guide structures are distributed on the substrate in a step shape, and the guide structures can transmit and guide light, can complete the photoelectric conversion process, and realize the integration of various optical waveguides and photoelectric conversion structures, thereby improving the monolithic integration of the waveguide integrated photoelectric detector.
Example one
An embodiment of the present invention provides a waveguide integrated type photodetector, as shown in fig. 1, where the waveguide integrated type photodetector includes a substrate, at least one optical waveguide 2, and a photoelectric conversion structure 3. The substrate may be a silicon substrate, a germanium substrate, a silicon-on-insulator substrate, or the like, which is not listed here.
The above-mentioned at least one optical waveguide 2 is formed above the substrate, each optical waveguide 2 including a guide portion 5, the guide portion 5 having a plurality of guide structures. At least two of the plurality of guide structures are distributed along a thickness direction of the substrate, and orthographic projection edges of two adjacent guide structures on the substrate are joined. At least one optical waveguide 2 is an optical waveguide formed by using a waveguide material. It should be understood that the number of the optical waveguides 2 and the relative positions between the optical waveguides 2 can be designed according to the practical application scenario, and are not limited in detail herein. As for the material contained in the optical waveguide 2, the waveguide material may be, specifically, any material capable of forming an optical waveguide2. Illustratively, the waveguide material may be amorphous, wherein the amorphous material may be Si3N4And the like.
The above-mentioned photoelectric conversion structure 3 is formed above the at least one optical waveguide 2 facing away from the substrate, and the guide portion 5 is used to guide light into the photoelectric conversion structure 3. It should be understood that the guide portion 5 has a plurality of guide structures. These guiding structures are distributed over the substrate in a step-like manner and are distributed in a direction gradually approaching the photoelectric conversion structure 3. The photoelectric conversion structure 3 may be formed above a guide structure closest to the photoelectric conversion structure 3 among the plurality of guide structures, so that the guide structure guides light into the photoelectric conversion structure 3. It can be seen that light can be conveniently guided into the photoelectric conversion structure 3 by modulating the spatial distribution of the plurality of guide structures.
As for the material contained in the photoelectric conversion structure 3, a photoelectric material is commonly used, and Ge, a quantum dot material, and the like.
As shown in fig. 1 and 2, when the waveguide-integrated type photodetector detects light emitted from the light source, each of the light waveguides 2 can receive light having an angle greater than 0 ° (about 8 °) with respect to the normal line of the substrate, and the light waveguide 2 includes a guide portion 5 having a plurality of guide structures capable of transmitting and guiding the light so that the light can be guided to the photoelectric conversion structure 3. Based on the photoelectric effect principle, the photoelectric conversion structure 3 absorbing the part of light can convert photons in the light into photon-generated carriers, thereby forming photocurrent in the photoelectric conversion structure 3. Finally, the photoelectric conversion structure 3 leads the generated photocurrent to photocurrent detection equipment, and the light detection process is completed.
In practical applications, when the optical waveguide 2 in the waveguide integrated type photodetector provided by the embodiment of the present invention contains Si as the material, the Si may be used as the material3N4And, when the material contained in the photoelectric conversion structure 3 may be Ge. Due to Si3N4The optical waveguide 2 has a higher refractive index, and the optical loss in the transmission process of the optical waveguide 2 can be reduced. At the same time, photoelectric conversion is enabled due to the presence of GeThe structure 3 has higher mobility of internal carriers after absorbing light, is convenient for converting the absorbed light into photocurrent, and improves the working performance of the waveguide integrated photoelectric detector. Compared with the existing waveguide integrated photoelectric detector composed of Si-based optical waveguide and Ge-based photoelectric conversion structure, the photoelectric detector is composed of Si3N4The waveguide integrated type photoelectric detector integrated by the optical waveguide 2 made of the material and the photoelectric conversion structure 3 made of the Ge material has lower transmission loss of the optical waveguide 2 and higher working performance.
As can be seen from the above optical detection process of the waveguide-integrated photodetector, in the waveguide-integrated photodetector provided in the embodiment of the present invention, each optical waveguide 2 includes the guiding portion 5, and the guiding portion 5 has a plurality of guiding structures, and at least two of the guiding structures are distributed along the thickness direction of the substrate. In other words, the plurality of guide structures are distributed over the substrate in a step shape, and are distributed in a direction gradually approaching the photoelectric conversion structure 3. The plurality of guide structures can sequentially transmit and guide light, so that the light can be guided into the photoelectric conversion structure 3 through the guide structure closest to the photoelectric conversion structure 3, and the photoelectric conversion process is completed. On this basis, the optical waveguide 2 including the plurality of guide structures is the optical waveguide 2 formed of a waveguide material including any waveguide material that can be used to form the optical waveguide 2, so that integration of the plurality of types of optical waveguides 2 and the photoelectric conversion structure 3 can be realized, and the monolithic integration of the waveguide-integrated photodetector can be improved.
In one example, the height direction of the above-described guide structure is defined to be the same as the thickness direction of the substrate. When the number of the guide structures is three, the heights of the three guide structures may be completely different, or the heights of two of the three guide structures may be different, and the specific height of the guide structure may be designed according to an actual application scenario, as long as the guide structure can be applied to the waveguide integrated type photodetector provided by the embodiment of the present invention.
Illustratively, as shown in fig. 5, the guide part 5 includes a first guide structure 6, a second guide structure 7 and a third guide structure 8 for connection.
Specifically, the first guide structure 6, the third guide structure 8, and the second guide structure 7 are distributed along the thickness direction of the substrate, and are distributed along a direction close to the photoelectric conversion structure 3. The first guide structure 6, the third guide structure 8 and the second guide structure 7 are still distributed along a direction close to the photoelectric conversion structure 3 in terms of the extending direction of the plane of the substrate surface.
In order to ensure that the light can be guided into the photoelectric conversion structure 3, the light incident surface of the photoelectric conversion structure 3 is located on one side of the light emitting surface of the second guiding structure 7 (i.e. the light incident surface of the photoelectric conversion structure 3 is located above the light emitting surface of the second guiding structure 7), so as to ensure that the light guided out by the guiding structure can accurately enter the photoelectric conversion structure 3.
In addition, the surface of the first guide structure 6 facing away from the substrate and the surface of the third guide structure 8 facing away from the substrate form an included angle of 90 ° to 170 °. The surface of the second guide structure 7 facing away from the substrate forms an angle of 90 ° to 170 ° with the surface of the third guide structure 8 facing away from the substrate. It will be appreciated that the light may change the direction of introduction into the photoelectric conversion structure 3 under the action of the third guide structure 8.
Illustratively, as shown in fig. 5, the surface of the first guide structure 6 facing away from the substrate forms an angle of 160 ° with the surface of the third guide structure 8 facing away from the substrate. The surface of the second guide structure 7 facing away from the substrate forms an angle of 160 with the surface of the third guide structure 8 facing away from the substrate. At this time, the light can change the direction of guiding into the photoelectric conversion structure 3 under the action of the third guiding structure 8, so as to achieve the purpose of guiding the light into the light incident surface of the photoelectric conversion structure 3 quickly.
As a possible implementation, as shown in fig. 1 and 5, each optical waveguide 2 further includes a grating portion 4. The grating portion 4 is used for diffracting the light, so that the diffracted light is coupled to the guide portion 5. It is understood that the grating portion 4 is capable of diffracting light and coupling the diffracted light to the guide portion 5. And the guide portion 5 can guide these diffracted light rays into the photoelectric conversion structure 3, thereby performing a photoelectric conversion process. The optical detection can be realized without arranging additional devices such as optical path alignment and the like, so that the structure of the waveguide integrated photoelectric detector is simpler.
In order to ensure that the light can be guided into the photoelectric conversion structure 3, the light incident surface of the guiding portion 5 is located on one side of the light emergent surface of the grating portion 4. The light incident surface of the photoelectric conversion structure 3 is located on one side of the light emergent surface of the guide portion 5. Specifically, when the guiding portion 5 includes the first guiding structure 6, the second guiding structure 7 and the third guiding structure 8, the light emitting surface of the grating portion 4 is located on one side of the light incident surface of the first guiding structure 6, so as to ensure that the light modulated by the grating portion 4 can accurately enter the first guiding structure 6.
Of course, in order to ensure diffraction accuracy, an optical fiber is formed on a substrate, and light is guided by the optical fiber to be accurately incident on the grating portion 4, thereby avoiding unnecessary light loss.
As shown in fig. 2 and fig. 5, the grating portion 4 may be an arc grating portion or a parallel slit grating portion, which satisfies the working requirement, and is not limited specifically herein. The specific specification of the grating portion 4 may be set according to practical situations, and is not particularly limited herein. The selection of the grating constant of the grating portion 4 affects the wavelength of the light incident into the guide portion 5. Specifically, if the incident light is diffracted into the guide portion 5 by the grating, the grating portion 4 needs to have a grating constant equal to the wavelength of the incident light. For example, if the incident light is infrared light, the grating constant of the grating portion 4 needs to be set to 760 nm to 1 mm.
As a possible implementation manner, as shown in fig. 1, the photoelectric conversion structure 3 may be a photoelectric conversion element such as a photodiode that meets the operation requirement.
Illustratively, as shown in fig. 1, the photoelectric conversion structure 3 includes a first electrode layer 21, a second electrode layer 23, and a photoelectric conversion layer 22 located between the first electrode layer 21 and the second electrode layer 23. The first electrode layer 21 is adjacent to the surface of the at least one optical waveguide 2 facing away from the substrate. It is to be understood that the photoelectric conversion layer 22 may absorb the light introduced by the guide 5, convert light energy contained in the light into electric energy, and form a photocurrent, and then transmit to the photocurrent detection device through the first electrode layer 21 and the second electrode layer 23.
As for the photoelectric conversion layer 22, the material contained in the photoelectric conversion layer 22 is a photoelectric material such as Ge, a quantum dot material, and the like which are common. The first electrode layer 21 and the second electrode layer 23 may be made of a semiconductor material doped with carriers (e.g., electrons or holes) or a metal conductive material. Illustratively, the material contained in the photoelectric conversion layer 22 is intrinsic Ge. The first electrode layer 21 is a germanium layer doped with P-type impurities. The second electrode layer 23 is a germanium layer doped with N-type impurities.
In an alternative mode, as shown in fig. 1, the photoelectric conversion structure 3 further includes an isolation layer 24 covering the surfaces of the first electrode layer 21 and the second electrode layer 23 facing away from the substrate, a first post 25 electrically connected to the first electrode layer 21 through the isolation layer 24, and a second post 26 electrically connected to the second electrode layer 23 through the isolation layer 24. It is to be understood that the presence of the separation layer 24 can protect the first electrode layer 21, the photoelectric conversion layer 22, and the second electrode layer 23 from etching or the like when the first post 25, the second post 26 are formed. The presence of the first terminal 25 and the second terminal 26 facilitates the photoelectric conversion structure 3 to lead out the generated photocurrent to the photocurrent detection device.
As a possible implementation, as shown in fig. 1 and 12, the waveguide integrated type photodetector further includes a light-transmissive bonding layer 20. The bonding layer 20 is located between the photoelectric conversion structure 3 and the at least one optical waveguide 2. It should be understood that when the waveguide integrated type photodetector further includes the light-transmissive bonding layer 20, the presence of the bonding layer 20 can increase the bonding strength when at least one optical waveguide 2 and the photoelectric conversion structure 3 are bonded together in the process of manufacturing the waveguide integrated type photodetector, thereby improving the structural stability of the waveguide integrated type photodetector. Meanwhile, the light-transmitting bonding layer 20 can transmit the light guided out from the light-emitting surface of the guide portion 5 into the photoelectric conversion layer 22, so that transmission loss is reduced.
As shown in fig. 1 and 12, the material contained in the bonding layer 20 may be selected according to actual conditions. Illustratively, the bonding layer 20 comprises a material that is a high dielectric constant oxide. Such as the common HfO2、ZrO2、TiO2、Al2O3And the like.
As a possible implementation manner, as shown in fig. 1, the waveguide integrated type photodetector further includes: a light-transmitting structure 9 formed on the surface of the substrate. At least one optical waveguide 2 is located in the light-transmitting structure 9, and the photoelectric conversion structure 3 is formed on a surface of the light-transmitting structure 9 facing away from the substrate. It will be appreciated that the presence of the light-transmitting structure 9 facilitates bonding of the at least one optical waveguide 2 and the photoelectric conversion structure 3 together when fabricating the waveguide integrated type photodetector. And, can protect at least one optical waveguide 2 from processes such as etching, doping, etc. in the course of bonding and subsequent fabrication.
As shown in fig. 1, for the light-transmitting structure 9, the material contained in the light-transmitting structure 9 is a light-transmitting material. The refractive index of the light-transmitting material may be lower than the refractive index of the material included in the light guide 2, so as to further reduce the light loss of the light guide 2 during light transmission. Such as common silica, high polymer materials, etc.
Illustratively, as shown in FIG. 1, to facilitate fabrication of at least one optical waveguide 2 within the light-transmissive structure 9. The light-transmitting structure 9 includes a first light-transmitting layer 10 and a second light-transmitting layer 11. A first light transmitting layer 10 is formed between the at least one optical waveguide 2 and the substrate. The second light transmitting layer 11 covers the surface of the at least one optical waveguide 2 and the first light transmitting layer 10 facing away from the substrate. The photoelectric conversion structure 3 is formed on the surface of the second light-transmitting layer 11 facing away from the substrate.
As shown in fig. 1 and 5, when the optical waveguide 2 described above includes the grating portion 4 and the guide portion 5, the grating portion 4 and the guide portion 5 are each formed on a surface of the first light-transmitting layer 10 facing away from the substrate. Specifically, when the guide portion 5 includes the first guide structure 6, the second guide structure 7, and the third guide structure 8, a step structure having an inclined surface is formed on the first light-transmitting layer 10. At this time, the first guide structure 6 is formed at the first height bearing surface of the step structure facing away from the substrate. The second guide structure 7 is formed at a second height bearing surface of the step structure facing away from the substrate. The third guiding structure 8 is formed at the inclined surface of the step structure facing away from the substrate. At this time, each portion of the guide portion 5 close to the substrate surface is attached to the surface of the first light-transmitting layer 10 away from the substrate, so that the guide portion 5 is formed on the surface of the first light-transmitting layer 10 away from the substrate.
Example two
An embodiment of the present invention provides a method for manufacturing a waveguide integrated photodetector, as shown in fig. 17, the method for manufacturing a waveguide integrated photodetector includes the following steps:
step S101, as shown in fig. 3, provides a first substrate 1. The first substrate 1 may be a silicon substrate, a germanium substrate, a silicon-on-insulator substrate, or the like, which is not listed here.
Step S102, as shown in fig. 4 and 5, forms at least one optical waveguide 2 above the first substrate 1, each optical waveguide 2 including a guide portion 5. The guide portion 5 has a plurality of guide structures, at least two of which are distributed along the thickness direction of the first substrate 1, and orthogonal projection edges of adjacent two guide structures on the first substrate 1 are joined. At least one optical waveguide 2 is an optical waveguide formed by using a waveguide material.
Illustratively, a waveguide material layer is formed above the first substrate 1, and at least one optical waveguide 2 is formed by performing dry etching or wet etching on the waveguide material layer. As for the material contained in the waveguide material layer and the layer thickness of the waveguide material layer, the material contained in the optical waveguide 2 and the forming parameters of the optical waveguide 2 can be referred to for setting, and details are not repeated herein.
Step S103, as shown in fig. 6 to 16, forms the photoelectric conversion structure 3 above the at least one optical waveguide 2 facing away from the first substrate 1. The guide portion 5 is for guiding light into the photoelectric conversion structure 3. As for the material and structure of the photoelectric conversion structure 3, reference is made to the foregoing description, and the description is omitted here.
The manufacturing method of the waveguide integrated type photodetector provided by the embodiment of the present invention has the same beneficial effects as those of the waveguide integrated type photodetector provided by the first embodiment, and details are not repeated herein.
In one example, as shown in fig. 5 and 16, the guide portion 5 includes a first guide structure 6, a second guide structure 7, and a third guide structure 8 for connection. The first guide structure 6, the third guide structure 8, and the second guide structure 7 are distributed along the thickness direction of the first substrate 1, and are distributed along a direction close to the photoelectric conversion structure 3. The first guide structure 6, the third guide structure 8 and the second guide structure 7 are still distributed along a direction close to the photoelectric conversion structure 3 in terms of the direction of extension of the plane in which the surface of the first substrate 1 lies.
Specifically, the light emitting surface of the second guiding structure 7 is opposite to the light incident surface of the photoelectric conversion structure 3. The surface of the first guide structure 6 facing away from the first substrate 1 forms an angle of 90 ° to 170 ° with the surface of the third guide structure 8 facing away from the first substrate 1. The surface of the second guide structure 7 facing away from the first substrate 1 forms an angle of 90 ° to 170 ° with the surface of the third guide structure 8 facing away from the first substrate 1.
Illustratively, as shown in fig. 5, the surface of the first guide structure 6 facing away from the first substrate 1 forms an angle of 160 ° with the surface of the third guide structure 8 facing away from the first substrate 1. The surface of the second guide structure 7 facing away from the first substrate 1 forms an angle of 160 ° with the surface of the third guide structure 8 facing away from the first substrate 1. At this time, the light can change the direction of guiding into the photoelectric conversion structure 3 under the action of the third guiding structure 8, so as to achieve the purpose of guiding the light into the light incident surface of the photoelectric conversion structure 3 quickly.
As a possible implementation, as shown in fig. 5 and 16, each optical waveguide 2 further includes a grating portion 4. The grating portion 4 is used for diffracting the light, so that the diffracted light is coupled to the guide portion 5. As for the specification setting of the grating portion 4, and the positional relationship of the grating portion 4 and the guide portion 5, the above settings can be referred to. Illustratively, when the guide portion 5 includes the first guide structure 6, the second guide structure 7 and the third guide structure 8, the light incident surface of the first guide structure 6 is adjacent to the light emergent surface of the grating portion 4.
As a possible implementation manner, as shown in fig. 4 and 5, after providing the first substrate 1, before forming the at least one optical waveguide 2 over the first substrate 1, the method for manufacturing the waveguide-integrated photodetector further includes:
in step S101-2, as shown in fig. 4, a first light-transmitting layer 10 is formed on the surface of the first substrate 1. The presence of the first light transmitting layer 10 may isolate the at least one optical waveguide 2 from the first substrate 1, preventing light from being transmitted into the first substrate 1 during transmission in the optical waveguide 2, thereby reducing transmission losses in the at least one optical waveguide 2.
Illustratively, when the first substrate 1 is a silicon substrate, the first light-transmitting layer 10 containing thermal silicon dioxide can be formed on the surface of the first substrate 1 by means of growth.
If the guide 5 comprises a first guide structure 6, a second guide structure 7 and a third guide structure 8. This guide portion 5 is formed on the first light-transmitting layer 10 for convenience in the subsequent process. It is necessary to perform etching or the like on the first light-transmitting layer 10 to form a step structure having an inclined surface on the surface of the first light-transmitting layer 10 away from the first substrate 1. Here, the specification of the step structure determines the specification of the third guide structure 8 to be formed on the inclined surface of the step structure, and thus, in order to attach each portion of the surface of the guide portion 5 close to the first substrate 1 to the surface of the first light-transmitting layer 10 away from the first substrate 1, the specification of the step structure should be set with reference to the specification of the third guide structure 8.
After forming the at least one optical waveguide 2 over the first substrate 1, and before forming the photoelectric conversion structure 3 over the at least one optical waveguide 2 away from the first substrate 1, the method for manufacturing the waveguide integrated type photodetector further includes:
in step S102-3a, as shown in fig. 6 and 7, a second light-transmitting layer 11 covering the at least one optical waveguide 2 is formed on a surface of the at least one optical waveguide 2 away from the first substrate 1, and the first light-transmitting layer 10 and the second light-transmitting layer 11 form a light-transmitting structure 9.
It will be appreciated that the presence of the light-transmitting structure 9 facilitates bonding of the at least one optical waveguide 2 and the photoelectric conversion structure 3 together when fabricating the waveguide integrated type photodetector. And, can protect at least one optical waveguide 2 from the influence of processing such as etching, doping in bonding and subsequent manufacturing process.
Illustratively, as shown in fig. 6 and 7, a silicon dioxide layer covering the at least one optical waveguide 2 is formed by growth on the surface of the at least one optical waveguide 2 facing away from the first substrate 1. After the silicon dioxide layer is formed, the top of the silicon dioxide layer is polished by a chemical mechanical polishing process or the like, so that the second light-transmitting layer 11 is formed. The surface of the second light-transmitting layer 11 away from the first substrate 1 is relatively flat, so that the photoelectric conversion structure 3 can be bonded on the surface of the second light-transmitting layer 11 away from the first substrate 1 in the following process.
As a possible implementation manner, as shown in fig. 8 to 16, after forming at least one optical waveguide 2 over the first substrate 1, before forming the photoelectric conversion structure 3 over the at least one optical waveguide 2 away from the first substrate 1, the method for manufacturing the waveguide integrated type photodetector further includes:
in step S102-3b.1a, a substrate 12 is provided. The base plate 12 includes a second substrate 13 and a photoelectric conversion structure 3 formed on the second substrate 13. As for the choice of the second substrate 13, reference may be made to the type of the first substrate 1 in the foregoing.
Illustratively, the photoelectric conversion structure 3 includes a first electrode layer 21, a second electrode layer 23, and a photoelectric conversion layer 22 located between the first electrode layer 21 and the second electrode layer 23. The second electrode layer 23, the photoelectric conversion layer 22, and the first electrode layer 21 are stacked over the second substrate 13 in a direction away from the second substrate 13.
As for the photoelectric conversion layer 22, the material contained in the photoelectric conversion layer 22 is a photoelectric material such as Ge, a quantum dot material, and the like which are common. The first electrode layer 21 and the second electrode layer 23 may be made of a semiconductor material doped with carriers (e.g., electrons or holes) or a metal conductive material. Illustratively, the material contained in the photoelectric conversion layer 22 is intrinsic Ge. The first electrode layer 21 is a germanium layer doped with P-type impurities. The second electrode layer 23 is a germanium layer doped with N-type impurities.
Step S102-3b.2a is to bond the photoelectric conversion structure 3 included in the substrate 12 and the at least one optical waveguide 2 together, obtaining the pre-integrated structure 18.
Step S102-3b.3a, the second substrate 13 comprised by the pre-integrated structure 18 is removed. Exemplarily, when the second substrate 13 is a silicon substrate. The silicon substrate included in the pre-integrated structure 18 is removed using a thinning process. And after the thinning process, etching the monocrystalline silicon remaining on the surface of the second electrode layer 23 with an acid solution.
It is noted that the base plate 12 may be provided as described above, including the second substrate 13 and the photoelectric conversion structure 3 formed on the second substrate 13. Furthermore, the substrate 12 may also be provided to include a second substrate 13 and a preformed structure 14 formed on the second substrate 13. The preformed structure 14 includes a second electrode forming layer 17, a photoelectric conversion forming layer 16, and a first electrode forming layer 15, which are sequentially stacked along the thickness direction of the second substrate 13 and located on the surface of the second substrate 13. Illustratively, the second electrode formation layer 17 and the photoelectric conversion formation layer 16 are intrinsic germanium layers. The first electrode forming layer 15 is a germanium layer doped with P-type impurities.
In one example, as shown in fig. 8 to 15, when the substrate 12 provided includes the second substrate 13 and the pre-formed structure 14, after forming the at least one optical waveguide 2 over the first substrate 1, and before forming the photoelectric conversion structure 3 over the at least one optical waveguide 2 away from the first substrate 1, the method for manufacturing the waveguide-integrated type photodetector further includes:
in step S102-3b.1b, as shown in fig. 8 to 11, a substrate 12 is provided. The base plate 12 comprises a second substrate 13 and a preformed structure 14 formed on the second substrate 13.
Step S102-3b.2b, as shown in fig. 12 and 13, bonds together the preformed structure 14 comprised by the substrate 12 and the at least one optical waveguide 2, obtaining the pre-integrated structure 18. It will be appreciated that the pre-integrated structure 18 is obtained in particular by bonding together the first electrode forming layer 15 in the pre-formed structure 14 and the at least one optical waveguide 2. The first electrode forming layer 15 is made to form the first electrode layer 21, and the photoelectric conversion forming layer 16 is made to form the photoelectric conversion layer 22.
Step S102-3b.3b, as shown in fig. 14, removes the second substrate 13 comprised by the pre-integrated structure 18. It is to be understood that after the second substrate 13 is removed, the second electrode formation layer 17 located under the second substrate 13 is exposed.
Step S102-3b.4b, as shown in fig. 15, an N-type impurity is implanted into the surface of the second electrode forming layer 17 facing away from the photoelectric conversion layer 22, so that the second electrode forming layer 17 forms the second electrode layer 23.
In an alternative, as shown in fig. 12 and 13, the substrate 12 further includes a buffer layer 19 between the second substrate 13 and the photoelectric conversion structure 3. It is to be understood that when the photoelectric conversion structure 3 is formed on the second substrate 13, the lattice difference between the material contained in the second substrate 13 and the material contained in the photoelectric conversion structure 3 is large. The large lattice difference causes the photoelectric conversion structure 3 formed directly on the second substrate 13 to have lattice defects, thereby affecting the operation performance of the waveguide-integrated type photodetector. And before the photoelectric conversion structure 3 is formed on the second substrate 13, a buffer layer 19 is formed on the second substrate 13. Because the difference between the crystal lattices of the materials contained in the buffer layer 19 and the photoelectric conversion structure 3 is small, the formed photoelectric conversion structure 3 can be prevented from having crystal lattice defects, and the performance of the waveguide integrated photoelectric detector is improved.
Illustratively, the buffer layer 19 is a Ge buffer layer, a SiGe buffer layer, a SiGeC buffer layer, a SiGeSn buffer layer, or the like. The thickness of the buffer layer 19 is not particularly limited as long as it can be set according to the actual situation.
When the substrate 12 further includes the buffer layer 19, the performance of the photoelectric conversion structure 3 is improved. After removing the second substrate 13 included in the pre-integrated structure 18 and before forming the photoelectric conversion structure 3 on the at least one optical waveguide 2 away from the first substrate 1, the method for manufacturing the waveguide-integrated type photodetector further includes:
step S102-3b.3-3, as shown in fig. 13 and 14, removes the buffer layer 19 comprised by the pre-integrated structure 18. It will be appreciated that the presence of the buffer layer 19 may nevertheless improve the quality of the photoelectric conversion structure 3 formed on the second substrate 13. However, since the crystal material in the buffer layer 19 has a large amount of surface defects, these defects cause leakage current in the photoelectric conversion structure 3, and affect the performance of the photoelectric conversion structure 3. Therefore, it is necessary to remove the buffer layer 19 after removing the second substrate 13, so that the dark current can be effectively reduced and the energy loss can be reduced.
Illustratively, the buffer layer 19 on the surface of the second electrode layer 23 is subjected to a chemical mechanical polishing process to polish away the buffer layer 19 on the surface of the second electrode layer 23.
At one kind canAlternatively, as shown in fig. 12 and 13, the bonding strength between the photoelectric conversion structure 3 and the at least one optical waveguide 2 is further improved. The substrate 12 further comprises a light-transmissive bonding layer 20, the bonding layer 20 being located between the photoelectric conversion structure 3 and the at least one optical waveguide 2. Illustratively, the bonding layer 20 comprises a material that is a high dielectric constant oxide. Such as the common HfO2、ZrO2、TiO2、Al2O3And the like.
When the substrate 12 further comprises the light-transmissive bonding layer 20, bonding the photoelectric conversion structure 3 comprised by the substrate 12 and the at least one optical waveguide 2 together, obtaining the pre-integrated structure 18 comprising:
step S102-3b.2.1, as shown in fig. 12 and 13, bonds the bonding layer 20 comprised by the substrate 12 and the at least one optical waveguide 2 together, obtaining the pre-integrated structure 18.
On this basis, when the waveguide integrated type photodetector further includes the light-transmitting structure 9, the step S102-3b.2.1 is to bond the bonding layer 20 included in the substrate 12 and the light-transmitting structure 9 together to obtain the pre-integrated structure 18.
In an alternative mode, as shown in fig. 16, the photoelectric conversion structure 3 further includes an isolation layer 24 covering the surfaces of the first electrode layer 21 and the second electrode layer 23 facing away from the first substrate 1, a first terminal 25 electrically connected to the first electrode layer 21 through the isolation layer 24, and a second terminal 26 electrically connected to the second electrode layer 23 through the isolation layer 24. It is to be understood that the presence of the separation layer 24 can protect the first electrode layer 21, the photoelectric conversion layer 22, and the second electrode layer 23 from etching or the like when the first post 25, the second post 26 are formed. The presence of the first terminal 25 and the second terminal 26 facilitates the photoelectric conversion structure 3 to lead out the generated photocurrent to the photocurrent detection device.
After the second electrode layer 23 is formed, the method for manufacturing the waveguide-integrated photodetector further includes:
step S102-3b.5b, forming a separation layer 24 covering the first electrode layer 21 and the second electrode layer 23 on the surface of the first electrode layer 21 and the second electrode layer 23 away from the first substrate 1.
Step S102-3b.3-3-3.2, a first contact hole and a second contact hole are formed in the isolation layer 24. The bottom of the first contact hole is in contact with the surface of the first electrode layer 21 facing away from the first substrate 1. The bottom of the second contact hole is in contact with the surface of the second electrode layer 23 facing away from the first substrate 1.
Step S102-3b.3-3-3.3, a first post 25 electrically connected to the first electrode layer 21 is formed in the first contact hole. A second post 26 electrically connected to the second electrode layer 23 is formed in the second contact hole.
It should be noted that, in order to improve the performance of the waveguide integrated photodetector, after the photoelectric conversion structure 3 is formed above at least one optical waveguide 2 away from the first substrate 1, the method for manufacturing the waveguide integrated photodetector further includes:
and step S104, carrying out alloy annealing treatment on the waveguide integrated type photoelectric detector.
In the foregoing description of embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.

Claims (13)

1. A waveguide-integrated photodetector, comprising:
a substrate;
the optical waveguide is formed above the substrate, each optical waveguide comprises a guide part, each guide part is provided with a plurality of guide structures, at least two of the guide structures are distributed along the thickness direction of the substrate, the orthographic projection edges of two adjacent guide structures on the substrate are jointed, and the at least one optical waveguide is made of a waveguide material;
the photoelectric conversion structure is formed above the at least one optical waveguide, which is far away from the substrate, and the guide part is used for guiding light into the photoelectric conversion structure; the photoelectric conversion structure is formed above the guide structure closest to the photoelectric conversion structure among the plurality of guide structures; the length extending direction of the guide structure positioned below the photoelectric conversion structure is parallel to the surface of the substrate;
the waveguide integrated type photoelectric detector further comprises a light-transmitting bonding layer, and the light-transmitting bonding layer is located between the photoelectric conversion structure and the at least one optical waveguide.
2. The waveguide-integrated photodetector of claim 1, wherein the guide portion comprises a first guide structure, a second guide structure, and a third guide structure for connection, wherein,
the surface of the first guide structure, which faces away from the substrate, and the surface of the third guide structure, which faces away from the substrate, form an included angle of 90-170 degrees;
the surface of the second guide structure, which faces away from the substrate, and the surface of the third guide structure, which faces away from the substrate, form an included angle of 90-170 degrees.
3. The waveguide-integrated photodetector of claim 1, wherein the at least one optical waveguide is an optical waveguide made of an amorphous waveguide material, the amorphous waveguide material comprising silicon nitride;
the photoelectric conversion structure is made of a photoelectric material.
4. The waveguide-integrated photodetector according to claim 1, wherein each of the optical waveguides further comprises a grating portion; the grating part is used for diffracting the light rays, so that the diffracted light rays are coupled to the guide part.
5. The waveguide-integrated photodetector according to claim 1, further comprising: the photoelectric conversion structure is formed on the surface, facing away from the substrate, of the light-transmitting structure, the at least one optical waveguide is located in the light-transmitting structure, and the photoelectric conversion structure is formed on the surface, facing away from the substrate, of the light-transmitting structure.
6. A method for manufacturing a waveguide integrated photoelectric detector is characterized by comprising the following steps:
providing a first substrate;
forming at least one optical waveguide above the first substrate, wherein each optical waveguide comprises a guide part, each guide part is provided with a plurality of guide structures, at least two of the guide structures are distributed along the thickness direction of the first substrate, the orthographic projection edges of two adjacent guide structures on the first substrate are jointed, and the at least one optical waveguide is made of a waveguide material;
forming a photoelectric conversion structure above the at least one optical waveguide and away from the first substrate, wherein the guide part is used for guiding light into the photoelectric conversion structure; the photoelectric conversion structure is formed above the guide structure closest to the photoelectric conversion structure among the plurality of guide structures; the length extending direction of the guide structure positioned below the photoelectric conversion structure is parallel to the surface of the substrate;
a light-transmitting bond and layer are formed between the photoelectric conversion structure and the at least one optical waveguide.
7. The method of claim 6, wherein the guiding portion comprises a first guiding structure, a second guiding structure and a third guiding structure for connection, wherein,
the surface of the first guide structure facing away from the first substrate and the surface of the third guide structure facing away from the first substrate form an included angle of 90-170 degrees;
the surface of the second guide structure, which faces away from the first substrate, and the surface of the third guide structure, which faces away from the first substrate, form an included angle of 90-170 degrees.
8. The method according to claim 6, wherein the at least one optical waveguide is an optical waveguide formed by using an amorphous waveguide material, and the amorphous waveguide material comprises silicon nitride;
the photoelectric conversion structure is made of a photoelectric material.
9. The method of claim 6, wherein each of the optical waveguides further comprises a grating portion; the grating part is used for diffracting the light rays, so that the diffracted light rays are coupled to the guide part.
10. The method of claim 6, wherein after the providing the first substrate, before the forming the at least one optical waveguide over the first substrate, the method further comprises:
forming a first light-transmitting layer over a surface of the first substrate;
after the at least one optical waveguide is formed over the first substrate and before the photoelectric conversion structure is formed over the at least one optical waveguide away from the first substrate, the method for manufacturing the waveguide-integrated photodetector further includes:
and forming a second light-transmitting layer covering the at least one optical waveguide on the surface of the at least one optical waveguide, which is far away from the first substrate, wherein the first light-transmitting layer and the second light-transmitting layer form a light-transmitting structure.
11. The method according to any one of claims 6 to 10, wherein after forming the at least one optical waveguide over the first substrate, before forming the photoelectric conversion structure over the at least one optical waveguide away from the first substrate, the method further comprises:
providing a substrate; the base plate comprises a second substrate and a photoelectric conversion structure formed on the second substrate;
bonding the photoelectric conversion structure included in the substrate and the at least one optical waveguide together to obtain a pre-integrated structure;
removing the second substrate included in the pre-integrated structure.
12. The method of fabricating a waveguide-integrated photodetector as claimed in claim 11, wherein the substrate further comprises a buffer layer between the second substrate and the photoelectric conversion structure;
after removing the second substrate included in the pre-integrated structure and before forming the photoelectric conversion structure above the at least one optical waveguide facing away from the first substrate, the method for manufacturing a waveguide-integrated photodetector further includes:
removing the buffer layer included in the pre-integrated structure.
13. The method of claim 11, wherein the substrate further comprises a light-transmissive bonding layer between the photoelectric conversion structure and the at least one optical waveguide;
the bonding together of the photoelectric conversion structure comprised by the substrate and the at least one optical waveguide to obtain a pre-integrated structure comprises:
and bonding the bonding layer included by the substrate and the at least one optical waveguide together to obtain a pre-integrated structure.
CN202010206294.9A 2020-03-23 2020-03-23 Waveguide integrated photoelectric detector and manufacturing method thereof Active CN111446309B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010206294.9A CN111446309B (en) 2020-03-23 2020-03-23 Waveguide integrated photoelectric detector and manufacturing method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010206294.9A CN111446309B (en) 2020-03-23 2020-03-23 Waveguide integrated photoelectric detector and manufacturing method thereof

Publications (2)

Publication Number Publication Date
CN111446309A CN111446309A (en) 2020-07-24
CN111446309B true CN111446309B (en) 2022-04-29

Family

ID=71655711

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010206294.9A Active CN111446309B (en) 2020-03-23 2020-03-23 Waveguide integrated photoelectric detector and manufacturing method thereof

Country Status (1)

Country Link
CN (1) CN111446309B (en)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111933753A (en) * 2020-08-14 2020-11-13 中国科学院微电子研究所 Waveguide type photoelectric detector and manufacturing method thereof
CN112186075B (en) * 2020-10-10 2023-05-23 中国科学院微电子研究所 Waveguide type photoelectric detector and manufacturing method thereof
CN113589524B (en) * 2021-10-08 2022-01-11 南昌大学 Design method of holographic grating optical waveguide planar light-gathering system for LiFi communication
CN114156350A (en) * 2021-11-30 2022-03-08 华进半导体封装先导技术研发中心有限公司 Three-dimensional detector structure and preparation method thereof
CN115295633A (en) * 2022-08-04 2022-11-04 赛丽科技(苏州)有限公司 Waveguide photoelectric detector integrated with antenna, system and method for sending signals

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5006906A (en) * 1988-08-29 1991-04-09 Bell Communications Research, Inc. Integrated semiconductor waveguide/photodetector
CN1141511A (en) * 1995-05-12 1997-01-29 富士通株式会社 Integrated optical module including waveguide and photoreception device
CN104090333A (en) * 2014-06-23 2014-10-08 天津工业大学 Binary blazed grating coupler and application thereof on silicon-based mixed integration photodetector
CN104412139A (en) * 2012-08-01 2015-03-11 日立化成株式会社 Optical fiber connector, method for manufacturing optical fiber connector, method for connecting optical fiber connector and optical fiber, and assembled body of optical fiber connector and optical fiber
CN207542269U (en) * 2018-01-31 2018-06-26 湖北光安伦科技有限公司 A kind of polarization correlation super-radiance light emitting diode chip
CN108231803A (en) * 2017-12-26 2018-06-29 中国电子科技集团公司第五十五研究所 Silicon nitride fiber waveguide device and graphene detector integrated chip and preparation method thereof
CN110854017A (en) * 2019-11-22 2020-02-28 中国科学院微电子研究所 Integration method of germanium-based detector
CN111933753A (en) * 2020-08-14 2020-11-13 中国科学院微电子研究所 Waveguide type photoelectric detector and manufacturing method thereof

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106024921B (en) * 2016-06-30 2017-09-15 浙江大学 Mounted model visible ray and near infrared band silicon substrate fiber waveguide integrated photodetector

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5006906A (en) * 1988-08-29 1991-04-09 Bell Communications Research, Inc. Integrated semiconductor waveguide/photodetector
CN1141511A (en) * 1995-05-12 1997-01-29 富士通株式会社 Integrated optical module including waveguide and photoreception device
CN104412139A (en) * 2012-08-01 2015-03-11 日立化成株式会社 Optical fiber connector, method for manufacturing optical fiber connector, method for connecting optical fiber connector and optical fiber, and assembled body of optical fiber connector and optical fiber
CN104090333A (en) * 2014-06-23 2014-10-08 天津工业大学 Binary blazed grating coupler and application thereof on silicon-based mixed integration photodetector
CN108231803A (en) * 2017-12-26 2018-06-29 中国电子科技集团公司第五十五研究所 Silicon nitride fiber waveguide device and graphene detector integrated chip and preparation method thereof
CN207542269U (en) * 2018-01-31 2018-06-26 湖北光安伦科技有限公司 A kind of polarization correlation super-radiance light emitting diode chip
CN110854017A (en) * 2019-11-22 2020-02-28 中国科学院微电子研究所 Integration method of germanium-based detector
CN111933753A (en) * 2020-08-14 2020-11-13 中国科学院微电子研究所 Waveguide type photoelectric detector and manufacturing method thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
应用于堆叠纳米线MOS器件的STI工艺优化研究;徐忍忍 等;《真空科学与技术学报》;20190131;第39卷(第1期);第65-70页 *

Also Published As

Publication number Publication date
CN111446309A (en) 2020-07-24

Similar Documents

Publication Publication Date Title
CN111446309B (en) Waveguide integrated photoelectric detector and manufacturing method thereof
US8269303B2 (en) SiGe photodiode
US10446707B2 (en) Optical waveguide detector and optical module
US9978890B1 (en) Germanium multi-directional detector
US8558336B2 (en) Semiconductor photodetector structure and the fabrication method thereof
KR100244048B1 (en) Optical semiconductor device and method of fabricating the same
US10914892B2 (en) Germanium photodetector coupled to a waveguide
US6307242B1 (en) Semiconductor photo-detector with square-shaped optical wave-guide
CN111211181B (en) Waveguide type photoelectric detector and manufacturing method thereof
JP2006522465A (en) Polycrystalline germanium-based waveguide detector integrated on thin-film silicon-on-insulator (SOI) platform
JP2019212820A (en) Optical semiconductor element and optical transmission device
KR20000023236A (en) An improved photodetector and device employing the photodetector for converting an optical signal into an electric signal
JP2008526003A (en) Germanium-on-silicon photodetector
US11735679B2 (en) Waveguide type photodetector and method of manufacture thereof
US8853812B2 (en) Photodetector, optical communication device equipped with the same, method for making of photodetector, and method for making of optical communication device
CN111668324A (en) Optical detector integrated with grating reflection structure
US20230197758A1 (en) Photodetecting device with enhanced collection efficiency
CN111129201A (en) Photoelectric detector
CN103000744A (en) Back-surface-incidence-type semiconductor light receiving element
JP6726248B2 (en) Semiconductor light receiving element and photoelectric fusion module
JP4094471B2 (en) Semiconductor photo detector
JP2008311562A (en) Light receiving element
CN114400267B (en) Photoelectric detector integrated with double absorption areas and preparation method thereof
CN117476800B (en) Silicon-based photoelectric detector and preparation method thereof
KR20010009571A (en) Photo-detector device and method manufacturing thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant