JPH04354327A - Device for epitaxially growing compound semiconductor - Google Patents

Abstract

PURPOSE:To extend the life of an HCl supply line and manufacture a compound semiconductor light emitting element whose Fe concentration is reduced by permitting a part from a filter to a gas supply port to be resin piping or piping whose interior is coated with ceramic or resin. CONSTITUTION:At least the part from a filter 28 to a gas supply port 6 among the HCl supply line 20 of the device, in other words, a connector 22 and a guide pipe 24, are permitted to be resin piping or piping whose interior is coated with ceramic or resin. Fluororesin is suitable for the resin for the piping and coating. The piping of the device does not corrode even the corrosive HCl gas is passed through. Contamination by Fe, etc., on the compound semiconductor substrate is suppressed and the life of the HCl supply line is extended.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a compound semiconductor epitaxial growth apparatus that can prevent corrosion on the inner surface of an HCl supply line, suppress contamination of compound semiconductor wafers with Fe, etc., and extend the life of the HCl supply line. .

0002

2. Description of the Related Art As one of the means for growing an epitaxial layer on a compound semiconductor substrate, for example, GaAsP is
HCl is supplied as a carrier gas for the Ga source to an apparatus for growing by PE (vapor phase epitaxial growth), and AsH3, AsH3,
Devices that supply PH3 are known. In this type of device, HCl gas exhibits corrosive properties due to trace amounts of moisture contained therein and H2O that inevitably enters when the piping is attached or detached. The reaction chamber in the epitaxial growth apparatus is made of quartz, and the gas supply port provided in this reaction chamber is also a quartz tube, so it will not corrode. However, since the piping of the HCl supply line is made of a corrodable material such as stainless steel, it is corroded by the passage of the above-mentioned corrosive HCl gas. These corroded Fe particles enter the reaction chamber and become mixed in the epitaxial layer, causing a problem in that the light emitting performance of a light emitting device using such a compound semiconductor is significantly reduced. To avoid such inconvenience,
It is necessary to clean the epitaxial growth equipment, especially the HCl supply line, in a complicated manner. If corrosion progressed, it was also necessary to replace the entire HCl supply line with a new one.

0003

[Problems to be Solved by the Invention] The present invention was invented in view of the problems of the prior art described above, and can prevent corrosion of the inner surface of the HCl supply line and suppress contamination of compound semiconductor wafers with Fe, etc. It is an object of the present invention to provide a compound semiconductor epitaxial growth apparatus that can extend the life of an HCl supply line, and a compound semiconductor light emitting device that has a reduced Fe concentration by using such an apparatus.

0004

[Means for Solving the Problems] In order to solve the above problems, the compound semiconductor epitaxial growth apparatus of the first invention of the present application has one end connected to a gas supply port provided in communication with a reaction chamber, and the other end portion connected to a gas supply port provided in communication with a reaction chamber. Equipped with an HCl supply line that supplies HCl gas into the reaction chamber through a filter provided, at least a portion of the HCl supply line from the filter to the gas supply port is resin piping or piping whose inside is coated with ceramic or resin. That is.

[0005] The above-mentioned resin needs to be heat resistant and highly pure, and fluororesins such as tetrafluoroethylene resin are particularly suitable.

[0006] There are no particular limitations on the quality of the ceramic material used for the ceramic coating, but TiO
2 is suitable, and known ceramic materials such as Cr2O3 and Al2O3 can be used.

[0007] The compound semiconductor light emitting device of the second invention of the present application includes:
The concentration of Fe at the pn junction interface and its vicinity is 1×1016
It is designed to be less than atoms/cc.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the apparatus of the present invention will be described below with reference to the accompanying drawings. In FIG. 1, 2 is a compound semiconductor epitaxial growth apparatus according to the present invention. The growth device 2
has a reaction chamber 4 made of quartz. On the supply side of the reaction chamber 4, a first gas supply port 6 and a second gas supply port 8 are connected to the reaction chamber 4.
They are connected to each other. These gas supply ports 6 and 8 are formed of quartz tubes. In this example,
An example has been shown in which HCl gas is supplied from the first gas supply port 6, and AsH3, PH3, and H2 are supplied from the second gas supply port 8.

Reference numeral 10 denotes a gas exhaust port provided on the exhaust side of the reaction chamber 4. 12 is a heater that heats the reaction chamber 4;

Reference numeral 14 denotes a quartz boat provided within the reaction chamber 4, in which, for example, a Ga source 16 is accommodated. 18
is a substrate support, on which the substrate W is set.

Reference numeral 20 denotes an HCl supply line, which includes a connector 22 connected to the first gas supply port 6, a guide tube 24 connected to the connector 22, an introduction tube 26 for introducing HCl gas, and the guide. It is formed from a pipe 24 and a filter 28 interposed between the introduction pipe 26.

A feature of the device of the present invention is that at least the portion of the HCl supply line 20 from the filter 28 to the gas supply port 6, in other words, the connector 22 and the guide tube 24 are coated inside with resin piping or ceramic or resin. The piping should be Of course, it is better if the introduction pipe 26 is a resin pipe or a pipe whose inside is coated with ceramic or resin.

[0013] The resin used for the resin piping or resin coating described above needs to be heat resistant and of high purity, and fluororesins such as tetrafluoroethylene resin are particularly suitable.

[0014] There are no particular limitations on the quality of the ceramic material used for the ceramic coating, but TiO
2 is suitable, and known ceramic materials such as Cr2O3 and Al2O3 can be used.

With the above configuration, the HCl supply line 20
Ga from the Ga source by flowing HCl gas from
is supplied as GaCl, and mixed with AsH3, PH3 and H2 supplied from the second gas supply port 8, and an epitaxial layer of GaAsP is grown on the substrate W.

In the apparatus of the present invention, since the HCl supply line 20 is a resin pipe or a pipe whose inside is coated with ceramic or resin, corrosive HC
The piping will not be corroded by the passage of l gas. Therefore, the problem of corroded Fe particles entering the reaction chamber, which was unavoidable in the case of conventional piping made of corrosive materials such as stainless steel, is solved, and Fe It is also possible to suppress pollution such as Furthermore, since the piping will not be corroded, the life of the HCl supply line will inevitably be extended.

A compound semiconductor light-emitting device with a small amount of Fe particles mixed in is produced using the above-described apparatus of the present invention, and a compound semiconductor light-emitting device with a large amount of Fe particles mixed in is produced using a conventional device for supplying HCl gas through stainless steel piping. FIG. 2 shows the results of an experiment conducted on the relationship between the Fe concentration and brightness at the pn junction interface and its vicinity after fabricating a light emitting device.

Note that in FIG. 2, the relative brightness (%) is S
It is displayed as a relative output value when the output at the lower limit of IMS detection (1×10 15 atoms/cc) is set as 100.

As is clear from FIG. 2, the Fe concentration at the pn junction interface and its vicinity is 1×10 16 atoms/c.
If it is less than c, there will be no decrease in brightness, but 1×1016a
It was found that the brightness significantly decreases when the value exceeds toms/cc.

Note that in the embodiment shown in FIG.
Although we have explained an example of a vapor phase epitaxial growth) device, HPE can also be used in an LPE (liquid phase epitaxial growth) device.
When cleaning is performed using the enching action of Cl gas, a method is adopted in which an HCl supply line is provided to supply HCl gas, so if the configuration of the device of the present invention is also adopted in the HCl supply line of the LPE device, Inconveniences caused by corrosion of pipes are likewise eliminated.

[0021]

As described above, according to the compound semiconductor epitaxial growth apparatus of the present invention, corrosion of the inner surface of the HCl supply line can be prevented, contamination of compound semiconductor substrates with Fe, etc. can be suppressed, and the life of the HCl supply line can be reduced. This makes it possible to manufacture a compound semiconductor light emitting device with a reduced Fe concentration.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing an embodiment of the device of the present invention.

FIG. 2 is a graph showing the relationship between Fe concentration and brightness in compound semiconductor light emitting devices produced by the apparatus of the present invention and the conventional apparatus, respectively.

[Explanation of symbols]

2 Compound semiconductor epitaxial growth apparatus 4 Reaction chamber 6 First gas supply port 8 Second gas supply port 16 Ga source 20 HCl supply line 22 Connector 24 Guide tube 26 Introduction tube 28 Filter W Substrate

Claims (3)

[Claims] 1. An HCl supply line having one end connected to a gas supply port provided in communication with the reaction chamber and supplying HCl gas into the reaction chamber through a filter provided at the other end, A compound semiconductor epitaxial growth apparatus characterized in that at least a portion of the supply line from the filter to the gas supply port is a resin pipe or a pipe whose inside is coated with ceramic or resin. 2. The compound semiconductor epitaxial growth apparatus according to claim 1, wherein the resin is a fluororesin. 3. A compound semiconductor light emitting device characterized in that the concentration of Fe at and near the pn junction interface is 1×10 16 atoms/cc or less.