CN108155254A - Two-dimensional material flexible substrate structure, focal plane photodetector array and production method - Google Patents

Abstract

The invention provides a two-dimensional material flexible substrate structure, a focal plane photodetector array and a manufacturing method. The two-dimensional material flexible substrate structure includes: a supporting substrate; a two-dimensional material layer located on the surface of the supporting substrate The patterned flexible substrate is located on the surface of the two-dimensional material layer; the patterned flexible substrate includes several pattern units distributed at intervals. The two-dimensional material flexible substrate structure of the present invention combines the patterned flexible substrate with the two-dimensional material layer, and the van der Waals bond at the interface between the patterned flexible substrate and the two-dimensional material layer greatly weakens the attraction between the upper and lower atoms Force, the strength of the van der Waals force formed at the interface is much smaller than the bond energy of the covalent bond, the patterned flexible substrate can completely self-adjust the strain absorption and release stress, and can eliminate or reduce the threading dislocation and other lattices to the greatest extent. Structural flaws, with a great deal of absolute flexibility.

Description

Two-dimensional material flexible substrate structure, focal plane photodetector array and manufacturing method

technical field

The invention belongs to the technical field of semiconductors, and relates to a two-dimensional material flexible substrate structure, a focal plane photodetector array and a manufacturing method.

Background technique

The short-wave infrared (SWIR, 1-3 micron) InGaAs focal plane detector array can meet the application requirements of "all-day, multi-weather". Civilian fields such as safety inspection, fire prevention warning, industrial inspection and driving vision enhancement have extensive and important application value1-3. InGaAs material has high quantum efficiency, good material stability, and can work at room temperature. The device performance of the same short-wave infrared band exceeds that of mercury cadmium telluride devices. The InGaAs detector has high imaging contrast, clear target details, and high recognition in target recognition. Due to the perfect match between the InGaAs absorption spectrum and the radiance band of the atmospheric glow at night, it has unique advantages in low-light night vision, and can obtain more abundant target imaging information than traditional technologies. Short-wave infrared is less affected by atmospheric scattering, and its ability to penetrate atmospheric obstacles such as smog and smoke is similar to thermal infrared, but there is no thermal imaging that is restricted by environmental heat crossover, and the image is clearer. In addition, the short-infrared InGaAs focal plane detector can also match 1.06 micron and 1.5x micron military lasers to realize stealthy active imaging technology for photoelectric countermeasures and photoelectric guidance.

At present, short-wave infrared mainly uses In _0.53 Ga _0.47 As materials with InP base and substrate matching, and its absorption wavelength ranges from 0.9 to 1.7 microns. By thinning the substrate to 0.2 microns, the lower limit of detection wavelength can be extended to the visible light region. At 0.7, 0.5 and 0.3 microns correspond to quantum efficiencies of 50%, 20% and 10%, respectively. After more than 20 years of development from prototype devices to products, FLIR and SUI in the United States have achieved 1920x1280 area arrays, and it is expected that the size of the area arrays will reach 2560x2048 in the next five years. By increasing the content of In in the InGaAs material, the absorption wavelength can theoretically reach 2.5 microns (indium component 0.82) and 3.5 microns (InAs). This extended wavelength InGaAs detector is mainly used for space remote sensing and multispectral imaging. However, due to the limitations of the substrate, the performance of the high-indium component InGaAs material decreases sharply with the increase of indium concentration. Currently, only CLPT in Taiwan, China has developed a 320x256 array product with a cut-off wavelength of 2.2 microns. The peak detection rate under 253K refrigeration conditions is The 1x10 ¹² Jones level is two orders of magnitude lower than the best peak detectability at room temperature of an In _0.53 Ga _0.47 As detector with a cutoff wavelength of 1.7 microns.

In principle, when the heterogeneous epitaxial material does not match the lattice constant of the substrate, there is a critical thickness of the epitaxial material. Within the thickness less than the critical thickness, the epitaxial heterogeneous material can achieve full strain without lattice defects. According to Matthews model ⁴ , for the epitaxial growth of In _x Ga _1-x As materials on InP substrates, the critical thickness, h _c , and the lattice mismatch, f, have the following relationship:

h _c ＝A[ln(h _c /b)+1]/f (1)

where b is the Burgers vector and A is a constant. When the lattice mismatch is greater than 0.5%, the critical thickness is only on the order of nanometers, while the thickness of the absorption layer of ordinary detectors is on the order of microns. When the epitaxial material is greater than the critical thickness, a large number of mismatches and threading dislocations will be generated. These bits Errors lead to serious dark currents and sharply degrade the performance of the detector. When the absorption wavelength reaches 2.5 microns (indium composition 0.82) and 3.5 microns (InAs), the mismatch degrees of InGaAs relative to InP are 2% and 3.2%, respectively. At present, the general idea of expanding InGaAs wavelength detectors based on InP is to use a mutation buffer layer, that is, to epitaxially grow a mutation buffer layer with a graded indium composition between the InP substrate and the high indium composition InGaAs absorber layer. Threading dislocations can be bent to suppress the threading dislocation density, but even with this method, the threading dislocation density is still around 10 ⁶ cm ^-2 , which is four times higher than the dislocation density of the InP substrate. order of magnitude, the corresponding InGaAs detector dark current is still very high, and the detection rate is low.

Flexible substrate is another epitaxial technology proposed by Y.H.Lo in 1991 to solve substrate mismatch6. The principle is shown in Figure 5. On a thin virtual substrate that can be freely extended, the epitaxial material whose lattice mismatch with the virtual substrate is grown, the elastic strain is shared by the virtual substrate and the epitaxial material, when the thickness of the epitaxial material exceeds the critical thickness and the thickness is much larger than the virtual When the thickness of the substrate is thicker, the stress-releasing dislocations are formed on the lower surface of the virtual substrate and slide to the interface to form misfit dislocations, and the threading dislocations at both ends of the misfit dislocations appear in the virtual substrate instead of the epitaxial material. Thin dummy substrates are generally achieved by bonding epitaxially grown dummy materials to a support substrate and then removing the epitaxial substrate by selective etching. This method has successfully achieved a high quality of 14.6% lattice mismatch on a GaAs substrate. InSb flexible substrate and its epitaxial material. However, the dangling bonds existing on the bonding surface will hinder the free extension of the flexible substrate. Only the flexible substrate with a small lateral size can fully realize the free extension. If the size is too large, surface wrinkles or other lattice defects will occur.

Contents of the invention

In view of the shortcomings of the prior art described above, the purpose of the present invention is to provide a two-dimensional material flexible substrate structure, focal plane photodetector array and manufacturing method, which are used to solve the problem of large area array photodetection in the prior art. The bottleneck of epitaxial growth technology is the crystal lattice mismatch encountered by the device, and the flexible substrate prepared by conventional means cannot completely absorb and release stress, and cannot meet the problem of absolute flexibility.

In order to achieve the above purpose and other related purposes, the present invention provides a two-dimensional material flexible substrate structure, the two-dimensional material flexible substrate structure includes:

supporting substrate;

a two-dimensional material layer located on the surface of the supporting substrate;

A patterned flexible substrate is located on the surface of the two-dimensional material layer; the patterned flexible substrate includes several pattern units distributed at intervals.

As a preferred solution of the two-dimensional material flexible substrate structure of the present invention, the two-dimensional material layer is a graphene layer, a silicene layer, a _germanene layer, a _tinene layer, a BN layer, a MoS2 layer, and a WS2 layer or GaSe layer.

As a preferred solution of the two-dimensional material flexible substrate structure of the present invention, the thickness of the patterned flexible substrate is less than or equal to 50 nm.

As a preferred solution of the two-dimensional material flexible substrate structure of the present invention, the graphic units are periodically distributed on the surface of the two-dimensional material layer.

As a preferred solution of the two-dimensional material flexible substrate structure of the present invention, the lateral dimension of the graphic unit is 0.1 μm˜100 μm.

The present invention also provides a method for manufacturing a two-dimensional material flexible substrate structure. The method for manufacturing a two-dimensional material flexible substrate structure includes the following steps:

1) providing a support substrate;

2) forming a two-dimensional material layer on the surface of the supporting substrate;

3) A patterned flexible substrate is formed on the surface of the two-dimensional material layer, and the patterned flexible substrate includes several pattern units distributed at intervals.

As a preferred solution of the manufacturing method of the two-dimensional material flexible substrate structure of the present invention, in step 2), the two-dimensional material layer is a graphene layer, a silicene layer, a germanene layer, a tinene layer, a BN layer, MoS ₂ layer, WS ₂ layer or GaSe layer.

As a preferred solution of the manufacturing method of the two-dimensional material flexible substrate structure of the present invention, in step 3), forming a patterned flexible substrate on the surface of the two-dimensional material layer includes the following steps:

3-1) providing a growth substrate;

3-2) forming a buffer layer on the growth substrate;

3-3) forming a sacrificial layer on the buffer layer;

3-4) forming a flexible substrate material layer on the sacrificial layer;

3-5) patterning the flexible substrate material layer to obtain the patterned flexible substrate;

3-6) bonding the structure obtained in step 3-5) to the surface of the two-dimensional material layer, the surface of the patterned flexible substrate being the bonding surface;

3-7) separating the patterned flexible substrate from the sacrificial layer, and transferring the patterned flexible substrate to the surface of the two-dimensional material layer.

As a preferred solution of the manufacturing method of the two-dimensional material flexible substrate structure of the present invention, between step 3-5) and step 3-6), it also includes passivating the surface of the patterned flexible substrate processing steps.

As a preferred solution of the manufacturing method of the two-dimensional material flexible substrate structure of the present invention, in step 3), forming a patterned flexible substrate on the surface of the two-dimensional material layer includes the following steps:

3-1) providing a growth substrate;

3-2) forming a buffer layer on the growth substrate;

3-3) forming a sacrificial layer on the buffer layer;

3-4) forming a flexible substrate material layer on the sacrificial layer;

3-5) bonding the structure obtained in step 3-4) to the surface of the two-dimensional material layer, the surface of the flexible substrate material layer being the bonding surface;

3-6) separating the flexible substrate material layer from the sacrificial layer, and transferring the flexible substrate material layer to the surface of the two-dimensional material layer;

3-7) Patterning the flexible substrate material layer transferred to the surface of the two-dimensional material layer to obtain the patterned flexible substrate.

The present invention also provides a focal plane photodetector array, the focal plane photodetector array comprising:

A two-dimensional material flexible substrate structure as described in any of the above schemes;

The light detector structure is located on the surface of each pattern unit in the patterned substrate.

As a preferred solution of the focal plane photodetector array of the present invention, the focal plane photodetector array also includes:

indium pillars located on the surface of each photodetector structure;

The readout circuit is located on the surface of the indium pillar.

The present invention also provides a method for manufacturing a focal plane photodetector array, and the method for manufacturing the focal plane photodetector array includes the following steps:

1) Fabricate the two-dimensional material flexible substrate structure by using the method for fabricating the two-dimensional material flexible substrate structure as described in any of the above schemes;

2) A photodetector structure is formed on the surface of each pattern unit in the patterned substrate.

As a preferred solution of the fabrication method of the focal plane photodetector array of the present invention, after step 2), it also includes forming an indium column on the surface of each photodetector, and forming a readout circuit on the surface of the indium column. step.

As mentioned above, the two-dimensional material flexible substrate structure, focal plane photodetector array and manufacturing method of the present invention have the following beneficial effects:

1) The two-dimensional material flexible substrate structure of the present invention combines the patterned flexible substrate with the two-dimensional material layer, and the van der Waals bond at the interface between the patterned flexible substrate and the two-dimensional material layer greatly weakens the bond between the upper and lower atoms. The strength of the van der Waals force formed at the interface is much smaller than the bond energy of the covalent bond. The patterned flexible substrate can completely self-adjust the strain absorption and release stress, and can eliminate or reduce threading dislocations to the greatest extent. Lattice structure defects, with great absolute flexibility;

2) The focal plane photodetector array of the present invention is based on a patterned flexible substrate. For the focal plane photodetector array, there is no array size limitation, and it is easy to realize a 1k×1k or even larger area array; the focal plane photodetector array The detection array has the advantages of greatly eliminating dislocation defects, reducing device dark current, increasing the size of area array devices, expanding wavelengths, reducing costs, and increasing device integration functions;

3) The manufacturing method of the present invention can be applied to wafer-level dimensions, is suitable for industrial production, and reduces production costs.

4) The present invention provides great flexibility for realizing high-performance heterojunction materials, is applicable to various material systems, and can realize various large-size focal plane photodetector arrays with a wide range of wavelengths.

Description of drawings

FIG. 1 shows a schematic structural view of a two-dimensional material flexible substrate structure provided in Embodiment 1 of the present invention.

FIG. 2 is a flow chart of a method for fabricating a two-dimensional material flexible substrate structure provided in Embodiment 2 of the present invention.

FIG. 3 to FIG. 14 show the structural schematic diagrams in each step of the manufacturing method of the two-dimensional material flexible substrate structure provided in the second embodiment of the present invention.

FIG. 15 is a schematic structural diagram of the focal plane photodetector array provided in Embodiment 3 of the present invention.

FIG. 16 is a flow chart of a method for fabricating a two-dimensional material flexible substrate structure provided in Embodiment 4 of the present invention.

FIG. 17 to FIG. 18 are schematic structural diagrams of various steps in the manufacturing method of the two-dimensional material flexible substrate structure provided in Embodiment 4 of the present invention.

Component designation description

10 Supporting substrate

11 Layers of 2D material

12 Patterned Flexible Substrates

121 graphics units

13 Growth substrate

14 buffer layer

15 sacrificial layer

16 layers of flexible substrate material

17 Photodetector structure

18 indium column

19 Readout circuit

Detailed ways

Embodiments of the present invention are described below through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific implementation modes, and various modifications or changes can be made to the details in this specification based on different viewpoints and applications without departing from the spirit of the present invention.

See Figures 1 through 18. It should be noted that the diagrams provided in this embodiment are only schematically illustrating the basic concept of the present invention, although only the components related to the present invention are shown in the diagrams rather than the number, shape and Dimensional drawing, the type, quantity and proportion of each component can be changed arbitrarily during actual implementation, and the component layout type may also be more complicated.

Embodiment one

Please refer to Fig. 1, the present invention provides a kind of two-dimensional material flexible substrate structure, and described two-dimensional material flexible substrate structure comprises: support substrate 10; Two-dimensional material layer 11, described two-dimensional material layer 11 is positioned at described The surface of the supporting substrate 10; the patterned flexible substrate 12, the patterned flexible substrate 12 is located on the surface of the two-dimensional material layer 11; the patterned flexible substrate 12 includes several pattern units 121 distributed at intervals. The two-dimensional material flexible substrate structure of the present invention combines the patterned flexible substrate 12 with the two-dimensional material layer 11, and the interface between the patterned flexible substrate 12 and the two-dimensional material layer 11 The van der Waals bond greatly weakens the attraction between the upper and lower atoms, and the strength of the van der Waals force formed at the interface is much smaller than the energy of the covalent bond. The patterned flexible substrate 12 can fully self-adjust strain absorption and releasing stress, can eliminate or reduce lattice structure defects such as threading dislocations to the greatest extent, and has great absolute flexibility; the flexible substrate of the two-dimensional material can be used for the substrate of a large area array focal plane photodetector array The focal plane photodetector array prepared on it has the advantages of greatly eliminating dislocation defects, reducing device dark current, increasing the size of area array devices, expanding wavelengths, reducing costs, and increasing device integration functions.

As an example, the supporting substrate 10 may be a semiconductor substrate, a semi-insulator substrate, an insulator substrate, a thermally conductive material substrate or a metal substrate. Preferably, in this embodiment, the supporting substrate 10 is a Si substrate.

As an example, the two-dimensional material layer 11 may be a graphene layer, a silicene layer, a germanene layer, a tinne layer, a BN layer, a MoS ₂ layer, a WS ₂ layer or a GaSe layer. Preferably, in this embodiment, the two-dimensional material layer 11 is a graphene layer.

As an example, the lattice constant of the flexible substrate 12 matches or adapts to the lattice constant of the semiconductor light-emitting device material layer to be formed on its surface; Lattice-matched or lattice-mismatched group IV, group III-V, group II-VI, group IV-VI or other semiconductor crystal materials; in examples, the flexible substrate 12 can be but not limited to n-type InGaAs flexible The substrate, more specifically, the flexible substrate 12 may be an n-type In _0.7 Ga _0.3 As flexible substrate or an n-type In _0.7 Ga _0.3 As flexible substrate.

As an example, the thickness of the patterned flexible substrate 12 may be selected according to actual needs. Preferably, in this embodiment, the thickness of the patterned flexible substrate 12 is less than or equal to 50 nm.

As an example, the graphic units 121 are periodically distributed on the surface of the two-dimensional material layer 11 . Of course, in other examples, the graphic units 121 may also be distributed aperiodically on the surface of the two-dimensional material layer 11 .

As an example, the lateral size of the graphic unit 121 can be set according to actual needs. Preferably, the lateral size of the graphic unit 121 is 0.1 μm to 100 μm; the distance between adjacent graphic units 121 can be set according to the actual It needs to be set and is not limited here. In an example, the lateral size of the graphic units 121 is 27 μm, and the distance between the centers of adjacent graphic units 121 is 30 μm.

As an example, the shape of the graphics unit 121 can be set according to actual needs, and the shape of the graphics unit 121 can be cylindrical, rectangular column, terraced, inverted terraced, etc., preferably, in this embodiment , the shape of the graphics unit 121 is a rectangular column.

Embodiment two

Please refer to Fig. 2, the present invention also provides a method for manufacturing a two-dimensional material flexible substrate structure, the method for manufacturing a two-dimensional material flexible substrate structure includes the following steps:

1) providing a support substrate;

2) forming a two-dimensional material layer on the surface of the supporting substrate;

3) A patterned flexible substrate is formed on the surface of the two-dimensional material layer, and the patterned flexible substrate includes several pattern units distributed at intervals.

Step 1) is performed, please refer to step S1 in FIG. 2 and FIG. 3 , and a support substrate 10 is provided.

As an example, the supporting substrate 10 may be a semiconductor substrate, a semi-insulator substrate, an insulator substrate, a thermally conductive material substrate or a metal substrate. Preferably, in this embodiment, the supporting substrate 10 is a Si substrate.

Execute step 2), please refer to step S2 in FIG. 2 and FIG. 4 , and form a two-dimensional material layer 11 on the surface of the support substrate 10 .

As an example, the two-dimensional material layer 11 may be a graphene layer, a silicene layer, a germanene layer, a tinne layer, a BN layer, a MoS ₂ layer, a WS ₂ layer or a GaSe layer. Preferably, in this embodiment, the two-dimensional material layer 11 is a graphene layer.

Execute step 3), please refer to step S3 in Fig. 2 and Fig. 5 to Fig. 14, form a patterned flexible substrate 12 on the surface 11 of the two-dimensional material layer, and the patterned flexible substrate 12 is composed of several Graphical units 121 distributed at intervals.

In an example, forming the patterned flexible substrate 12 on the surface of the two-dimensional material layer 11 includes the following steps:

3-1) A growth substrate 13 is provided, as shown in FIG. 5; the material of the growth substrate 13 can be Si, Ge, GaAs, InP, GaSb, InAs, InSb, SiC, AlN, GaN or sapphire, etc. ;

3-2) forming a buffer layer 14 on the growth substrate 13, as shown in FIG. 6;

3-3) forming a sacrificial layer 15 on the buffer layer 14, as shown in FIG. 7; the material of the sacrificial layer 15 is a material that can be easily removed by selective etching or oxidation;

3-4) Form a flexible substrate material layer 16 on the sacrificial layer 15, as shown in FIG. Phase Epitaxy) forms the flexible substrate material layer 16 on the surface of the sacrificial layer 15; specifically, the lattice constant of the flexible substrate material layer 16 is consistent with the lattice constant of the semiconductor light emitting device material layer to be formed on its surface The constants are matched or adapted; the material of the flexible substrate material layer 16 can be group IV, group III-V, group II-VI, group IV-VI or Other semiconductor crystal materials; in this example, the flexible substrate material layer 16 can be a doped flexible substrate material layer, or an undoped flexible substrate material layer; the flexible substrate material layer 16 The thickness can be selected according to actual needs, preferably, in this embodiment, the thickness of the flexible substrate material layer 16 is less than or equal to 50nm;

3-5) Patterning the flexible substrate material layer 16 to obtain the patterned flexible substrate 12, as shown in FIG. 9; The shape of the substrate 12, and then use an etching process to remove part of the flexible substrate material layer 16 to obtain the patterned flexible substrate 12; preferably, the etching stop layer in the etching process is the growth substrate Bottom 13, that is, in the etching process, part of the buffer layer 14 and part of the sacrificial layer 15 are removed, and only the buffer layer 14 and the sacrificial layer 15 located directly below the graphic unit 121 are retained, as shown in FIG. 9 ; Specifically, the graphic units 121 obtained after the graphic processing are periodically distributed on the surface of the two-dimensional material layer 11; of course, in other examples, the graphic units 121 can also be distributed The surface is non-periodically distributed; the lateral size of the graphic unit 121 can be set according to actual needs, preferably, the lateral size of the graphic unit 121 is 0.1 μm to 100 μm; the distance between adjacent graphic units 121 It can be set according to actual needs, and is not limited here. In one example, the lateral dimension of the graphic unit 121 is 27 μm, and the distance between the centers of adjacent graphic units 121 is 30 μm; the shape of the graphic unit 121 can be set according to actual needs, and the graphic The shape of the unit 121 can be cylindrical, rectangular column, terraced, inverted terraced, etc., preferably, in this embodiment, the shape of the graphic unit 121 is a rectangular column;

3-6) Bonding the structure obtained in step 3-5) to the surface of the two-dimensional material layer 11, the surface of the patterned flexible substrate 12 being the bonding surface, as shown in FIG. 10 ;

3-7) Using a wet etching process to separate the patterned flexible substrate 12 from the sacrificial layer 15, and transfer the patterned flexible substrate 12 to the surface of the two-dimensional material layer 11, as shown in FIG. 11.

As an example, between step 3-5) and step 3-6), a step of passivating the surface of the patterned flexible substrate 12 is also included.

Please refer to FIGS. 12 to 14. In another example, the flexible substrate material layer 16 may be transferred to the surface of the two-dimensional material layer 11 before patterning the flexible substrate material layer 16. To obtain the patterned flexible substrate 12 .

Next, a specific example is used to further illustrate the method for manufacturing the two-dimensional material flexible substrate structure described in this embodiment, which specifically includes the following steps:

(1) A 200nm InP buffer layer was grown on an n-type InP substrate by molecular beam epitaxy at a growth temperature of 520°C;

(2) Epitaxially grow a 100nm lattice-matched In _0.52 Al _0.48 As sacrificial layer on the InP buffer layer at a growth temperature of 520°C;

(3) Epitaxial growth of 15nm silicon-doped n-type In _0.7 Ga _0.3 As film on the In _0.52 Al _0.48 As sacrificial layer, the doping concentration is on the order of 2x10 ¹⁸ cm ^-3 and the growth temperature is 480°C;

(4) Use photolithography to realize a square array of 1k x 1k, with a center-to-center spacing of 30 microns and a mesa side length of 27 microns, and the etching depth stops at the InP substrate interface;

(5) Realize single atomic layer graphene on silicon base;

(6) Area-array bonding of n-type In _0.7 Ga _0.3 As flexible substrate with In _0.52 Al _0.48 As sacrificial layer to silicon-based graphene;

(7) Selective wet etching is used to separate the InP substrate to form an n-type In _0.7 Ga _0.3 As flexible substrate array.

Embodiment Three

Please refer to Fig. 15, the present invention also provides a focal plane photodetector array, the focal plane photodetector array includes: the two-dimensional material flexible substrate structure as described in the first embodiment, the two-dimensional material flexible For the specific structure of the substrate structure, please refer to Embodiment 1, which is no longer similar here; the photodetector structure 17, the photodetector structure 17 is located on the surface of each pattern unit 121 in the patterned substrate 12, that is, the The photodetector structure 17 is a structure distributed in a periodic array.

As an example, the photodetector structure 17 may be, but not limited to, a 2.5 micron photodetector structure comprising an In _0.82 Ga _0.18 As absorbing layer.

As an example, the photodetector structure 17 may be a structure of upper and lower electrodes, or a structure of coplanar electrodes.

As an example, the focal plane photodetector array further includes: an indium column 18 located on the surface of each photodetector structure 17; a readout circuit 19 located on the indium column 18 surfaces.

Embodiment four

Please refer to FIG. 16 , the present invention also provides a method for manufacturing a focal plane photodetector array, and the method for manufacturing the focal plane photodetector array includes the following steps:

1) Fabricate the two-dimensional material flexible substrate structure using the method for fabricating the two-dimensional material flexible substrate structure as described in Embodiment 2;

2) A photodetector structure is formed on the surface of each pattern unit in the patterned substrate.

To perform step 1), please refer to step S1 in FIG. 16 , and use the method for fabricating a two-dimensional material flexible substrate structure as described in Embodiment 2 to fabricate the two-dimensional material flexible substrate structure.

As an example, please refer to Embodiment 2 for the specific method of manufacturing the flexible substrate structure of the two-dimensional material, and will not repeat it this time.

To execute step 2), please refer to step S2 in FIG. 16 and FIG. 17 to FIG. 18 , the photodetector structure 17 is formed on the surface of each pattern unit 121 in the patterned substrate 12 .

As an example, the photodetector structure can be formed on the surface of each pattern unit 121 in the patterned substrate 12 by using an epitaxial molecular beam epitaxy process (Molecular Beam Epitaxy) or a metal organic chemical vapor deposition process (Metalorganic Vapor Phase Epitaxy) 17.

As an example, the photodetector structure 17 may be prepared by using a process of upper and lower electrodes or coplanar electrodes.

As an example, step 2) further includes the step of forming an indium column 18 on the surface of each of the photodetectors 17 , and forming a readout circuit 19 on the surface of the indium column 18 .

Next, a specific example is used to further illustrate the method for manufacturing the focal plane photodetector array described in this embodiment, which specifically includes the following steps:

(1) A 200nm InP buffer layer was grown on an n-type InP substrate by molecular beam epitaxy at a growth temperature of 520°C;

(2) Epitaxially grow a 100nm lattice-matched In _0.52 Al _0.48 As sacrificial layer on the InP buffer layer at a growth temperature of 520°C;

(3) Epitaxial growth of 15nm silicon-doped n-type In _0.7 Ga _0.3 As film on the In _0.52 Al _0.48 As sacrificial layer, the doping concentration is on the order of 2x10 ¹⁸ cm ^-3 and the growth temperature is 480°C;

(4) Use photolithography to realize a square array of 1k x 1k, with a center-to-center spacing of 30 microns and a mesa side length of 27 microns, and the etching depth stops at the InP substrate interface;

(5) Realize single atomic layer graphene on silicon base;

(6) Area-array bonding of n-type In _0.7 Ga _0.3 As flexible substrate with In _0.52 Al _0.48 As sacrificial layer to silicon-based graphene;

(7) Selective wet etching is used to separate the InP substrate to form an n-type In _0.7 Ga _0.3 As flexible substrate array;

(8) On the n-type In _0.7 Ga _0.3 As flexible substrate array, a 2.5 micron photodetector structure containing an In _0.82 Ga _0.18 As absorption layer was grown by molecular beam epitaxy;

(9) forming an indium pillar on the surface of each of the photodetectors, and forming a readout circuit on the surface of the indium pillar.

In summary, the present invention provides a two-dimensional material flexible substrate structure, a focal plane photodetector array, and a manufacturing method. The two-dimensional material flexible substrate structure includes: a supporting substrate; a two-dimensional material layer located on the The surface of the support substrate; the patterned flexible substrate is located on the surface of the two-dimensional material layer; the patterned flexible substrate includes several graphic units distributed at intervals. The two-dimensional material flexible substrate structure of the present invention combines the patterned flexible substrate with the two-dimensional material layer, and the van der Waals bond at the interface between the patterned flexible substrate and the two-dimensional material layer greatly weakens the attraction between the upper and lower atoms Force, the strength of the van der Waals force formed at the interface is much smaller than the bond energy of the covalent bond, the patterned flexible substrate can completely self-adjust the strain absorption and release stress, and can eliminate or reduce the threading dislocation and other lattices to the greatest extent. Structural flaws, with a great deal of absolute flexibility.

The above-mentioned embodiments only illustrate the principles and effects of the present invention, but are not intended to limit the present invention. Anyone skilled in the art can modify or change the above-mentioned embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical ideas disclosed in the present invention shall still be covered by the claims of the present invention.

Claims (14)

1. a kind of two-dimensional material flexible substrate structure, which is characterized in that including：

Support substrate；

Two-dimensional material layer, positioned at the support substrate surface；

Patterned flex, positioned at the two-dimensional material layer surface；The patterned flex is to include several intervals The graphic element of distribution.

2. two-dimensional material flexible substrate structure according to claim 1, it is characterised in that：The two-dimensional material layer is graphite Alkene layer, silene layer, germanium alkene layer, tin alkene layer, BN layers, MoS₂Layer, WS₂Layer or GaSe layers.

3. two-dimensional material flexible substrate structure according to claim 1, it is characterised in that：The patterned flex Thickness is less than or equal to 50nm.

4. two-dimensional material flexible substrate structure according to claim 1, it is characterised in that：The graphic element is described two It is in periodic distribution to tie up material surface.

5. two-dimensional material flexible substrate structure according to claim 1, it is characterised in that：The lateral ruler of the graphic element Very little is 0.1 μm~100 μm.

6. a kind of production method of two-dimensional material flexible substrate structure, it is characterised in that：Include the following steps：

1) a kind of support substrate is provided；

2) two-dimensional material layer is formed on the surface of the support substrate；

3) patterned flex is formed in the two-dimensional material layer surface, the patterned flex is to include several Every the graphic element of distribution.

7. the production method of two-dimensional material flexible substrate structure according to claim 6, it is characterised in that：In step 2) In, the two-dimensional material layer is graphene layer, silene layer, germanium alkene layer, tin alkene layer, BN layers, MoS₂Layer, WS₂Layer or GaSe layers.

8. the production method of two-dimensional material flexible substrate structure according to claim 6, it is characterised in that：In step 3) In, it forms patterned flex in the two-dimensional material layer surface and includes the following steps：

A kind of growth substrates 3-1) are provided；

3-2) buffer layer is formed in the growth substrates；

3-3) sacrificial layer is formed on the buffer layer；

Flexible substrate material layer 3-4) is formed on the sacrificial layer；

The flexible substrate material layer 3-5) is patterned processing, to obtain the patterned flex；

3-6) by step 3-5) obtained structure is bonded to the surface of the two-dimensional material layer, the table of the patterned flex Face is bonding face；

3-7) patterned flex and the sacrificial layer are separated, the patterned flex is transferred to described The surface of two-dimensional material layer.

9. the production method of two-dimensional material flexible substrate structure according to claim 8, it is characterised in that：In step 3-5) With step 3-6) between, further include the step of processing is passivated to the surface of the patterned flex.

10. the production method of two-dimensional material flexible substrate structure according to claim 6, it is characterised in that：In step 3) In, it forms patterned flex in the two-dimensional material layer surface and includes the following steps：

A kind of growth substrates 3-1) are provided；

3-2) buffer layer is formed in the growth substrates；

3-3) sacrificial layer is formed on the buffer layer；

Flexible substrate material layer 3-4) is formed on the sacrificial layer；

3-5) by step 3-4) obtained structure is bonded to the surface of the two-dimensional material layer, the table of the flexible substrate material layer Face is bonding face；

3-6) the flexible substrate material layer and the sacrificial layer are separated, the flexible substrate material layer is transferred to described The surface of two-dimensional material layer；

The flexible substrate material layer that 3-7) will transfer to the two-dimensional material layer surface is patterned processing, to obtain State patterned flex.

11. a kind of focal plane photodetector array, which is characterized in that including：

Two-dimensional material flexible substrate structure as described in any one of claim 1 to 5；

Optical detector structure, the surface of each graphic element in the patterned substrate.

12. focal plane photodetector array according to claim 11, it is characterised in that：The focal plane optical detector battle array Row further include：

Indium column, positioned at each optical detector body structure surface；

Reading circuit, positioned at the indium column surface.

13. a kind of production method of focal plane photodetector array, it is characterised in that：Include the following steps：

1) using as described in the production method making of the two-dimensional material flexible substrate structure as described in any one of claim 6 to 10 Two-dimensional material flexible substrate structure；

2) surface of each graphic element forms optical detector structure in the patterned substrate.

14. the production method of focal plane photodetector array according to claim 13, it is characterised in that：Step 2) it After be additionally included in each optical detector surface and form indium column, and the step of form reading circuit on the indium column surface.