CN-121992494-A - Method for manufacturing semiconductor device

Abstract

The present invention has an object to provide a method for manufacturing a semiconductor device capable of reducing or removing Si atoms at an interface between a substrate or a semiconductor layer made of InP or InGaAsP and another semiconductor layer grown thereon. The manufacturing method of the present invention is a method for manufacturing a semiconductor device (1) including a first semiconductor (2) composed of InP or InGaAsP and a second semiconductor (3) provided on the first semiconductor (2). The manufacturing method includes a first step and a second step. In the first step, the surface of the first semiconductor (2) is thermally cleaned in a growth furnace (C) set to an atmosphere containing arsine. In the second step, a second semiconductor (3) is grown on the surface of the first semiconductor (2) in a growth furnace (C). The set temperature in the thermally cleaned growth furnace (C) is made lower than the set temperature in the growth furnace (C) when the second semiconductor (3) is grown.

Inventors

• SENBA TAKASHI
• OKUMURA KOJI

Assignees

• 浜松光子学株式会社

Dates

Publication Date

20260508

Application Date

20251106

Priority Date

20241108

Claims (11)

1. 1. A method of manufacturing a semiconductor device, wherein, The semiconductor device includes a first semiconductor made of InP or InGaAsP, and a second semiconductor provided on the first semiconductor, The method for manufacturing a semiconductor device comprises the steps of: a step of performing a thermal cleaning of the surface of the first semiconductor in a growth furnace set to an atmosphere containing arsine, and A step of growing the second semiconductor on the surface of the first semiconductor in the growth furnace, The set temperature in the growth furnace of the thermal cleaning is made lower than the set temperature in the growth furnace when the second semiconductor is grown.
2. 2. The method for manufacturing a semiconductor device according to claim 1, wherein, The temperature of the first semiconductor of the thermal cleaning is made lower than 534 ℃.
3. 3. The method for manufacturing a semiconductor device according to claim 1, wherein, The temperature of the first semiconductor of the thermal cleaning is set to 476 ℃ or less.
4. 4. The method for manufacturing a semiconductor device according to claim 1 or 2, wherein, The temperature of the first semiconductor of the thermal cleaning is set to 417 ℃ or higher.
5. 5. The method for manufacturing a semiconductor device according to claim 1, wherein, The temperature of the first semiconductor of the thermal cleaning is set to 417 ℃ to 476 ℃.
6. 6. The method for manufacturing a semiconductor device according to any one of claims 1 to 5, wherein, The treatment time for the heat washing is set to 30 minutes or longer.
7. 7. The method for manufacturing a semiconductor device according to any one of claims 1 to 6, wherein, In the heat washing, the total supply amount of arsine is set to 50% or more relative to the volume of the growth furnace.
8. 8. The method for manufacturing a semiconductor device according to any one of claims 1 to 7, wherein, The root mean square roughness of the surface of the first semiconductor after the heat cleaning is 0.3nm or less.
9. 9. The method for manufacturing a semiconductor device according to any one of claims 1 to 8, wherein, The time of the thermal cleaning is longer than the growth time of the second semiconductor.
10. 10. The method for manufacturing a semiconductor device according to any one of claims 1 to 9, wherein, Between the step of performing the thermal cleaning and the step of growing the second semiconductor, Further comprising a step of heating the growth furnace by setting the interior of the growth furnace to an atmosphere containing phosphine instead of arsine, And (3) making the flow rate of the heat-cleaned arsine be larger than the flow rate of the phosphine in the heating step.
11. 11. The method for manufacturing a semiconductor device according to any one of claims 1 to 10, wherein, The first semiconductor is composed of (InP) 1-z (In 0.53 Ga 0.47 As) z (0≤z < 1).

Description

Method for manufacturing semiconductor device Technical Field The present disclosure relates to a method of manufacturing a semiconductor device. Background Patent document 1 discloses a vapor phase growth method for performing crystal growth on an InP substrate. In this method, phosphine (PH 3) gas is supplied at 5X 10 -3 mol/min or more before crystal growth starts, and the InP substrate is heated to 700 ℃ or more. Patent document 2 discloses a surface treatment method and a semiconductor device. Patent document 3 discloses a semiconductor laser and a method for manufacturing the same. Prior art literature Patent literature Patent document 1 Japanese patent laid-open No. 1-197398 Patent document 2 Japanese patent application laid-open No. 2000-124138 Patent document 3 Japanese patent laid-open No. 11-204877 Disclosure of Invention Problems to be solved by the invention In general, in a semiconductor device such as a High Electron Mobility Transistor (HEMT) formed of a GaAs-based semiconductor, an undoped epitaxial layer is grown on a substrate. At this time, if silicon (Si) impurities are present at the interface of the epitaxial layer and the substrate, the epitaxial layer has conductivity, and the electrical characteristics of the semiconductor device deteriorate due to current leakage or the like. In order to improve such problems, various studies have been made on semiconductor devices made of GaAs-based semiconductors. On the other hand, when another semiconductor layer is grown on a substrate or semiconductor layer made of InP or InGaAsP, unintended incorporation of Si atoms occurs at the interface between the substrate or semiconductor layer and the other semiconductor layer. For example, in the case of manufacturing a photodiode made of an InP-based semiconductor, there is a problem that the element capacity is undesirably increased by the incorporation of Si atoms. Accordingly, it is desirable to reduce or remove Si atoms at the interface of the substrate or semiconductor layer and the further semiconductor layer. In general, when a semiconductor is grown on an InP substrate, a heat treatment is performed in an atmosphere of phosphine (PH 3) which is a group V source gas of a substrate material in order to remove a natural oxide film on the InP substrate. However, in the heat treatment under the atmosphere of pH 3, it is difficult to eliminate Si atoms. An object of the present disclosure is to provide a method of manufacturing a semiconductor device capable of reducing or removing Si atoms at an interface of a substrate or semiconductor layer composed of InP or InGaAsP and another semiconductor layer grown thereon. Means for solving the problems [1] A method of manufacturing a semiconductor device according to one aspect of the present disclosure is a method of manufacturing a semiconductor device including a first semiconductor made of InP or InGaAsP and a second semiconductor provided on the first semiconductor. The manufacturing method includes a first step and a second step. In the first step, the surface of the first semiconductor is thermally cleaned in a growth furnace in which an atmosphere containing arsine is set. In the second step, the second semiconductor is grown on the surface of the first semiconductor in a growth furnace. The set temperature in the thermally cleaned growth furnace is made lower than the set temperature in the growth furnace at the time of growing the second semiconductor. The present inventors have found that by performing thermal cleaning under an arsine (AsH 3) atmosphere, si atoms present on the surface of a substrate or semiconductor layer made of InP or InGaAsP can be eliminated. In addition, when the surface of a semiconductor made of InP or InGaAsP is thermally cleaned, if the substrate temperature is increased, P atoms are separated by thermal degradation of InP or InGaAsP, and In atoms are deposited. When the heat cleaning is performed In an AsH 3 atmosphere, the P atoms are released and the As atoms are replaced, whereby the As atoms are bonded to the In atoms, and foreign matter is generated on the surface. Therefore, the set temperature in the thermally cleaned growth furnace is made lower than the set temperature in the growth furnace at the time of growing the second semiconductor. This can prevent thermal degradation of InP or InGaAsP, reduce P atom detachment, and reduce the generation of foreign matter. As a result of the above, according to the manufacturing method of [1], it is possible to reduce the generation of foreign matter at the interface of the substrate made of InP or InGaAsP, or the semiconductor layer, i.e., the first semiconductor, and the other semiconductor layer grown thereon, i.e., the second semiconductor, and to reduce or remove Si atoms. [2] In the method of manufacturing the semiconductor device of the above item [1], the temperature of the thermally cleaned first semiconductor may be set to be lower than 534 ℃. In this cas