Silicon-based hybrid multiple quantum well structure and preparation method thereof

Abstract

The present invention discloses a silicon-based hybrid multiple quantum well structure, which includes a buffer layer and at least one combination layer sequentially disposed on a substrate; the combination layer includes a barrier layer and a quantum well layer of BGaAsBi material, and the material composition of the quantum well layer satisfies: B x Ga 1‑ x As 1‑y Bi y , x≥5%, y≥5%. The quantum well layer is closer to the buffer layer than the barrier layer. On the premise of ensuring silicon-based light emission, the present invention can greatly alleviate lattice mismatch, and can overcome thermal mismatch and polar mismatch; thereby improving the quality of semiconductor materials, and can be applied and contribute to the quality improvement of high-speed microelectronic devices.

Description

Technical Field

[0001] The present invention belongs to the field of semiconductor technology, and in particular relates to a silicon-based hybrid multi-quantum well structure and a preparation method thereof. Background Art

[0002] Optoelectronic integration technology is conducive to high-speed signal transmission and has attracted more and more attention. Optoelectronic integration technology is developing in three directions: first, high speed and high performance, achieving low noise, high bandwidth, and large dynamic range to meet the needs of end users for high-speed data transmission; second, array-based large-scale integration, which can meet the backbone network's needs for a significant speed increase; third, multifunctional signal processing, integrating complex signal processing functions such as signal generation, judgment, emission, and detection on a single chip. The key technology of optoelectronic integration is undoubtedly the integration technology of photonic integrated devices and high-speed microelectronic devices.

[0003] The development of high-speed microelectronic devices based on silicon has achieved great success. Silicon is the most important and widely used semiconductor material and the foundation of the field of microelectronics and integrated circuits. However, the development of photonic integrated devices based on silicon has encountered difficulties. Silicon is an indirect bandgap material and is difficult to emit light by itself. Therefore, preparing or integrating other materials on a silicon substrate to achieve luminescence is usually the method of choice. Materials that can directly emit light, such as III-V groups, are epitaxially grown on silicon substrates, but problems such as lattice mismatch, polarity mismatch, and thermal mismatch are encountered. Researchers have tried epitaxial growth of a variety of light-emitting materials on silicon substrates, but none of them have achieved good results. Summary of the invention

[0004] The technical problem to be solved by the present invention is to overcome the defect in the prior art that mismatch easily occurs in the preparation or integration of light-emitting materials on a silicon substrate, and to provide a silicon-based hybrid multiple quantum well structure and a preparation method thereof.

[0005] The present invention solves the above technical problems through the following technical solutions:

[0006] The present invention provides a silicon-based hybrid multi-quantum well structure, comprising a buffer layer and at least one combination layer sequentially arranged on a substrate; the combination layer comprises a barrier layer and a potential well layer of a BGaAsBi material, and the material composition of the potential well layer satisfies:

[0007] B x Ga 1-x As 1-y Bi y , where x ≥ 5%, y ≥ 5%;

[0008] The potential well layer is closer to the buffer layer than the potential barrier layer.

[0009] Preferably, the buffer layer and the barrier layer are made of Si material.

[0010] Preferably, the number of the combined layers is no more than 5.

[0011] Preferably, the potential well layer has a thickness of 5nm-10nm.

[0012] Preferably, the barrier layer has a thickness of 10 nm-20 nm.

[0013] Preferably, the carrier concentration of the potential well layer is less than 3×10 16 cm -3 ;

[0014] and / or,

[0015] The carrier concentration of the barrier layer doping is less than 3×10 16 cm -3 .

[0016] Preferably, the material of the potential well layer is B 0.06 Ga 0.94 As 0.92 Bi 0.08 .

[0017] Preferably, the material of the potential well layer is B 0.1 Ga 0.9 As 0.9 Bi 0.1 .

[0018] The present invention also provides a method for preparing a silicon-based hybrid multi-quantum well structure, which is used to prepare the above-mentioned silicon-based hybrid multi-quantum well structure. The preparation method comprises the following steps:

[0019] epitaxially growing a buffer layer on the substrate;

[0020] A plurality of combined layers are grown on the buffer layer; the combined layers include a barrier layer and a potential well layer of BGaAsBi material, and the material composition of the potential well layer satisfies:

[0021] B x Ga 1-x As 1-y Bi y , where x ≥ 5%, y ≥ 5%;

[0022] The potential well layer is closer to the buffer layer than the potential barrier layer.

[0023] Preferably, the number of the combined layers is 1-5.

[0024] The positive progressive effect of the present invention is that the present invention provides a silicon-based hybrid multiple quantum well structure and a preparation method thereof, which can greatly alleviate the lattice mismatch and overcome the thermal mismatch and polarity mismatch while ensuring silicon-based luminescence; thereby improving the quality of semiconductor materials, and can be applied to and contribute to the quality improvement of high-speed microelectronic devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Schematic diagram of the structure of a silicon-based hybrid multiple quantum well structure according to an embodiment of the present invention.

[0026] Figure 2 The figure is a flow chart of a method for preparing a silicon-based hybrid multiple quantum well structure according to an embodiment of the present invention.

[0027] Figure 3 The silicon-based B of the embodiment of the present invention 0.06 Ga 0.94 As 0.92 Bi 0.08 Schematic diagram of the structure of / Si multiple quantum well structure.

[0028] Figure 4 The silicon-based B of the embodiment of the present invention 0.1 Ga 0.9 As 0.9 Bi 0.1 Schematic diagram of the structure of / Si multiple quantum well structure. DETAILED DESCRIPTION

[0029] The present invention is further described below by way of examples, but the present invention is not limited to the scope of the examples.

[0030] See also Figure 1 As shown, this embodiment provides a silicon-based hybrid multi-quantum well structure, including a buffer layer 2 and at least one combination layer 3 sequentially arranged on a substrate 1; the combination layer 3 includes a potential well layer 31 and a barrier layer 32 of BGaAsBi material, and the material composition of the potential well layer 31 satisfies:

[0031] B x Ga 1-x As 1-y Bi y , where x ≥ 5%, y ≥ 5%;

[0032] The well layer 31 is closer to the buffer layer 2 than the barrier layer 32 .

[0033] The combined layer 3 on the substrate 1 of the Si material of this embodiment, i.e., the BGaAsBi / Si multi-quantum well structure, can realize silicon-based luminescence. The potential well layer 31 of the BGaAsBi material is a direct band gap and has a small lattice mismatch with the Si substrate. The potential well layer 31 of the BGaAsBi material is thin and can withstand the thermal mismatch with the Si substrate. The corresponding potential well layer 31 and barrier layer 32 are grown respectively by metal organic chemical vapor deposition and molecular beam epitaxy methods. Annealing under H atmosphere in the metal organic chemical vapor deposition chamber can form diatomic steps on the surface of the Si material, overcome the influence of polarity mismatch, and realize high-quality materials.

[0034] As a preferred embodiment, the buffer layer 2 and the barrier layer are made of Si material.

[0035] As a preferred embodiment, the number of the combined layers 3 is no more than five.

[0036] As a preferred embodiment, the thickness of the potential well layer 31 is 5 nm-10 nm.

[0037] As a preferred embodiment, the thickness of the barrier layer 32 is 10 nm-20 nm.

[0038] As a preferred embodiment, the carrier concentration of the potential well layer 31 is less than 3×10 16 cm -3 ;

[0039] The carrier concentration of the barrier layer 32 is less than 3×10 16 cm -3 .

[0040] As a preferred embodiment, the material of the potential well layer 31 is B 0.06 Ga 0.94 As 0.92 Bi 0.08 .

[0041] As a preferred embodiment, the material of the potential well layer 31 is B 0.1 Ga 0.9 As 0.9 Bi 0.1 .

[0042] See also Figure 2 As shown, a silicon-based hybrid multi-quantum well structure is prepared by the following preparation method, comprising the steps of:

[0043] S1. Epitaxially grow a buffer layer on a substrate.

[0044] S2. Growing several combined layers on the buffer layer; the combined layers include a barrier layer and a potential well layer of BGaAsBi material, and the material composition of the potential well layer satisfies: B x Ga1-x As 1-y Bi y , where x ≥ 5%, y ≥ 5%;

[0045] The potential well layer is closer to the buffer layer than to the potential barrier layer.

[0046] See also Figure 3 As a preferred embodiment, this embodiment shows a silicon-based B 0.06 Ga 0.94 As 0.92 Bi 0.08 / Si multi-quantum well structure, including:

[0047] 1. Si buffer layer grown by molecular beam epitaxy, thickness 200nm.

[0048] 2. Metal organic chemical vapor deposition growth of B 0.06 Ga 0.94 As 0.92 Bi 0.08 Potential well layer, thickness 8nm.

[0049] 3. Si barrier layer grown by molecular beam epitaxy, thickness 20nm.

[0050] 4. Aforementioned B 0.06 Ga 0.94 As 0.92 Bi 0.08 The quantum well structure period of the potential well layer and the Si barrier layer is 3. Those skilled in the art will understand that 0.06 Ga 0.94 As 0.92 Bi 0.08 The quantum well structure composed of the potential well layer and the Si barrier layer is the above-mentioned combined layer.

[0051] 5. The above materials are not doped.

[0052] Preparation of the above silicon-based B 0.06 Ga 0.94 As 0.92 Bi 0.08 The steps of / Si multi-quantum well structure are as follows:

[0053] S1', the Si substrate is introduced into the cavity of the molecular beam epitaxy growth chamber, the Si substrate is degassed and deoxidized, and a 200 nm thick Si buffer layer is grown by molecular beam epitaxy method.

[0054] S2', after the growth stops, the sample is cooled to room temperature. The sample is transferred to a metal organic chemical vapor deposition chamber under a vacuum environment, and the material is annealed in a H atmosphere.

[0055] S3', using metal organic chemical vapor deposition to grow 8nm thick B 0.06 Ga 0.94 As 0.92 Bi 0.08 Quantum well materials.

[0056] S4', after the growth stops, the sample is cooled to room temperature, the metal organic chemical vapor deposition chamber is evacuated, and then the sample is transferred to the molecular beam epitaxy chamber under vacuum.

[0057] S5', grow a 20 nm thick Si barrier layer using molecular beam epitaxy.

[0058] S6', repeat the above steps 2 to 5 twice in sequence, and complete the growth of a total of 3 periods of quantum well structure, ie, combination layer.

[0059] See also Figure 4 As a preferred embodiment, this embodiment also shows a silicon-based B 0.1 Ga 0.9 As 0.9 Bi 0.1 / Si multi-quantum well structure, including:

[0060] 1. Si buffer layer grown by molecular beam epitaxy, thickness 500nm, undoped.

[0061] 2. Metal organic chemical vapor deposition growth of B 0.1 Ga 0.9 As 0.9 Bi 0.1 Potential well layer, thickness 5nm, n-type carrier concentration is about 1×10 16 cm -3

[0062] 3. Molecular beam epitaxially grown Si barrier layer, thickness 15nm, undoped

[0063] 4. Repeat step B above 0.1 Ga 0.9 As 0.9 Bi 0.1 The potential well layer and the Si barrier layer are formed twice to form a quantum well structure of three periods. 0.1 Ga 0.9 As 0.9 Bi 0.1 The quantum well structure composed of the potential well layer and the Si barrier layer is the above-mentioned combined layer.

[0064] Preparation of the above silicon-based B 0.06 Ga 0.94 As 0.92 Bi 0.08 The steps of / Si multi-quantum well structure include:

[0065] S1”, the Si substrate is introduced into the molecular beam epitaxy growth chamber, the Si substrate is degassed and deoxidized, and a 500nm thick undoped Si buffer layer is grown by molecular beam epitaxy;

[0066] S2”, after the growth stops, the sample is cooled to room temperature. The sample is transferred to a metal organic chemical vapor deposition chamber under a vacuum environment, and the material is annealed in a H atmosphere;

[0067] S3”, using metal organic chemical vapor deposition to grow 5nm thick B 0.1 Ga 0.9 As 0.9 Bi 0.1 Quantum well materials, SiH 4 As a doping material, the n-type carrier concentration is about 1×10 16 cm -3 ;

[0068] S4”, after the growth stops, the sample is cooled to room temperature, and the metal organic chemical vapor deposition chamber is evacuated. Then the sample is transferred to the molecular beam epitaxy chamber under vacuum;

[0069] S5”, using molecular beam epitaxy to grow a 15nm thick undoped Si barrier layer;

[0070] S6”, repeat the above steps 2-5 twice, and complete the growth of 3 cycles of B 0.1 Ga 0.9 As 0.9 Bi 0.1 / Si quantum well structure.

[0071] This embodiment provides a silicon-based hybrid multiple quantum well structure and a preparation method thereof, which greatly alleviates lattice mismatch and overcomes thermal mismatch and polarity mismatch while ensuring silicon-based luminescence; thereby improving the quality of semiconductor materials, and can be applied to and contribute to improving the quality of high-speed microelectronic devices.

[0072] Although the specific embodiments of the present invention are described above, it should be understood by those skilled in the art that this is only for illustration and the protection scope of the present invention is defined by the appended claims. Those skilled in the art may make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but these changes and modifications all fall within the protection scope of the present invention.

Claims

1. A silicon-based hybrid multiple quantum well structure, It is characterized in that The invention comprises a buffer layer and at least one combination layer which are sequentially arranged on a substrate; the combination layer comprises a barrier layer and a potential well layer of a BGaAsBi material, and the material composition of the potential well layer satisfies: B x Ga 1-x As 1-y Bi y , where x ≥ 5%, y ≥ 5%; The potential well layer is closer to the buffer layer than the potential barrier layer.

2. The silicon-based hybrid multiple quantum well structure according to claim 1, It is characterized in that The buffer layer and the barrier layer are made of Si material.

3. The silicon-based hybrid multi-quantum well structure according to claim 1, It is characterized in that The number of the combined layers is no more than 5.

4. The silicon-based hybrid multiple quantum well structure according to claim 1, It is characterized in that The potential well layer has a thickness of 5nm-10nm.

5. The silicon-based hybrid multiple quantum well structure as claimed in claim 1, It is characterized in that The barrier layer has a thickness of 10 nm to 20 nm.

6. The silicon-based hybrid multiple quantum well structure according to claim 1, It is characterized in that The carrier concentration of the potential well layer and / or the potential barrier layer is less than 3×10 16 cm -3 .

7. The silicon-based hybrid multiple quantum well structure according to claim 1, It is characterized in that The material of the potential well layer is B 0.06 Ga 0.94 As 0.92 Bi 0.08 .

8. The silicon-based hybrid multiple quantum well structure as claimed in claim 1, It is characterized in that The material of the potential well layer is B 0.1 Ga 0.9 As 0.9 Bi 0.1 .

9. A method for preparing a silicon-based hybrid multi-quantum well structure, It is characterized in that For preparing the silicon-based hybrid multi-quantum well structure as claimed in claim 1, the preparation method comprises the following steps: epitaxially growing a buffer layer on the substrate; A plurality of combined layers are grown on the buffer layer; the combined layers include a barrier layer and a potential well layer of BGaAsBi material, and the material composition of the potential well layer satisfies: B x Ga 1-x As 1-y Bi y , where x ≥ 5%, y ≥ 5%; The potential well layer is closer to the buffer layer than the potential barrier layer.

10. The method for preparing a silicon-based hybrid multiple quantum well structure according to claim 9, It is characterized in that The number of the combined layers is 1 to 5.

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