JPS5877226A - Luquid phase epitaxial growth device - Google Patents

Abstract

PURPOSE:To improve productivity by shortening the preparatory processing time for epitaxial growth by a method wherein desired gas is supplied and a spare chamber controlled at about 300 deg.C is also provided at a part of the inlet and outlet of a growth chamber applied heating control here through a gate. CONSTITUTION:A gas supply pipe 9 and a gas exhaust pipe 11 are provided at the one end section of a quartz tube 1 for epitaxial growth surrounded by temperature controllig heaters 2 and the side wall of the other end respectively and a gate 3 freely sliding up and down is also slided at the opening section of the exhaust pipe 11. Next, while sliding the gate 3 in the same way, a spare chamber 4 having a gas supply pipe 10 and a gas exhaust pipe 12 at the front end and the heel of the side wall respectivly is positioned and the first slide 8 sliding a boat 5 by penetrating a cap 6 closing the opening section and the second slide 7 sliding a substrate and a source solution reservoir are provided. Before growing an epitaxial layer on the substrate composed in this way, the temperature in the spare chamber 4 is firstly raisen at about 300 deg.C. After that, the gate 3 is opened to move the substrate or the like in the quartz tube 1.

Description

[Detailed description of the invention] The present invention relates to a liquid phase epitaxial growth apparatus.

Liquid phase epitaxial growth apparatuses are used in the formation of epitaxial layers in the manufacture of semiconductor devices, particularly light-emitting confectionery, semiconductor lasers, and the like.

In a conventional epitaxial growth apparatus, for example, a light emitting element substrate made of a compound semiconductor is fixed to a boat containing a growth source, and the boat is inserted into a growth chamber that is replaced with hydrogen at room temperature. Next, after replacing the boat with hydrogen for one hour, the growth chamber was raised to the baking temperature and left for a certain period of time, and then raised to the preheat temperature and left for a certain period of time. Thereafter, impurities are grown on the substrate while moving the boat containing the reaction solution while lowering the temperature at a rate of 0.1 to 0.5 G/min. When growth is complete, the temperature of the growth chamber is lowered to room temperature in order to take out the boat. During this cycle operation, hydrogen is flowing into the growth chamber.

The problem with this method is that the net processing steps required for growth are a baking process, a preheating process, and a growth process; Although the 1st column is not needed for growth, it could not be omitted in the conventional method because the growth chamber is in a hydrogen atmosphere (attempting to take out the boat at a high temperature of 300 C or higher would cause an explosion). Therefore, one cycle takes 8 hours.

Accordingly, an object of the present invention is to provide a liquid phase epitaxial growth apparatus with short processing time and high productivity.

In order to achieve such an object, the present invention provides a growth chamber that is supplied with a desired gas and whose heating is controlled, a group of slides that control the processing object and the source placed in the growth chamber, and A liquid-phase epitaxial growth apparatus comprising a cap that closes the entrance and exit side of the chamber, and a low-temperature preliminary chamber is disposed in a part of the entrance and exit side of the growth chamber with a gate in between. Describe the invention.

FIG. 1 is a schematic diagram showing a liquid phase epitaxial growth apparatus according to an embodiment of the present invention, and FIG. 2 is a graph showing the temperature profile during processing.

In FIG. 4, l denotes a growth chamber formed by a quartz tube that accommodates a substrate to be processed and performs epitaxial growth. A motor 2 for temperature control is disposed at the outer edge of the growth chamber l. One end of the growth chamber 1 forms an entrance and exit port through which the boat 5 is inserted into and removed from the growth chamber 1. Further, the boat 5 and the solution reservoir containing the substrate and source mounted on the boat 5 are controlled by a group of slides such as the first slide 8 and the second slide 7. Further, the entrance/exit of the growth chamber 1 is airtightly attached with a cap 6. Further, a preliminary chamber 4 is provided on the entrance/exit side of the growth chamber 1 with a gate 3 in between. This spare room 4 is gate 3
When the cap 6 is removed after the cap 6 is closed, the temperature is controlled to be around 300 t:', which prevents hydrogen explosion, and under this condition, the boat 5 is connected to the preliminary chamber 4 and the atmosphere. Load between.

Unloading is done. Further, the growth chamber 1 and the preparatory chamber 4 are provided with gas supply pipes 9, 10 and exhaust pipes 11, respectively.
12 is arranged to create a predetermined gas atmosphere in the growth chamber 1 and the preparatory chamber 4.

In such an apparatus, when performing epitaxial growth, first, the boat 5 containing the source and substrate is placed in the preparatory chamber 4 which is insulated with hydrogen or nitrogen, and then kept for 1 hour as shown in FIG. Only hydrogen is replaced.

Next, the gate 3 is opened, and the boat 5 is moved by the first slide 8 of the growth chamber IK, which is controlled at a temperature T and has a hydrogen atmosphere. Then, with the gate 3 open, the temperature of the growth chamber 1 is changed from baking at T to preheating at T as shown in Figure 2, and a desired epitaxial layer is grown on the substrate within 12 hours. let

When the formation of the epitaxial layer is completed, the boat 5 is moved to the preliminary chamber 4 and the gate 3 is closed. At this time, the temperature of the preliminary chamber 4 and the growth chamber 1 is lowered (forcibly cooled by gas, cooling water, etc.). The growth chamber l is lowered to the bake temperature, and the preliminary chamber 4 is lowered to the baking temperature.
Descend to around ooc or below. When the temperature in the preliminary chamber 4 reaches around 300C or higher, the cap 6 is removed and the processed substrate and solution reservoir are removed (unloaded), a new substrate and solution reservoir are inserted (loaded), and the next operation is repeated. Start.

According to such an embodiment, a preparatory chamber is provided, and in this preparatory chamber, the temperature is lowered and raised with large temperature differences as in the conventional growth chamber, but the growth chamber in which epitaxial growth is performed is heated to a high temperature (above Tt). Maintained and managed. As a result, the temperature rising and cooling times can be shortened, so the working time for one cycle can be halved from the conventional 8 hours to 4 hours, and productivity can be doubled.

It should be noted that the present invention is not limited to the above-mentioned embodiments, but can be modified based on the technical idea of the present invention.

As described above, according to the present invention, it is possible to provide a liquid phase epitaxial growth apparatus with high productivity and short processing time.

[Brief explanation of the drawing]

@Figure 1 is a schematic diagram of the liquid phase epitaxial growth apparatus of the present invention, and Figure 2 is a graph showing the temperature history. Explanation of symbols l...Growth chamber, 2...Heater, 3...Gate, 4
... Spare room, 5... Boat, 6... Cap, 7
... 2nd slide, 8... 1st slide.

Claims (1)

[Scope of Claims] 1. A growth chamber that is supplied with a desired gas and whose heating is controlled; a slide group that controls the processing object and source placed in the growth chamber; and a cap that closes the entrance and exit side of the growth chamber. A liquid phase epitaxial growth apparatus comprising: a low-temperature preliminary chamber disposed in a part of the entrance/exit side of the growth chamber with a gate in between. 2. The liquid phase epitaxial growth apparatus according to claim 1, wherein the preliminary chamber is controlled at around 300t:'.