JPH08330395A - Substrate manipulator - Google Patents

Abstract

PURPOSE: To reduce a heavy metal contamination to a substrate and make the quality of a semiconductor thin film formed on the substrate good, by covering with quartz a heating source and the portions of their temperatures being increased through the heating source. CONSTITUTION: In a substrate manipulator for performing the substrate heating of the device for forming a semiconductor thin film in a vacuum, a heating source 3 opposed to a substrate 6 and the portions of their temperatures being increased by the heating source 3 are covered with quartz to reduce a heavy metal contamination to the substrate 6. For example, the heating portion of the substrate manipulator has several sheets of thermal shield plates 9 on an SiC heater 3, and is fastened to a thermal insulation plate 10 made of alumina. The thermal insulation plate 10 is fastened to a metallic plate 12 via a spacer 11, and the whole of the heating portion has the structure of it being held by a holder 13. Further, the whole of the heating portion comprising the SiC heater 3 and the thermal shield plates 9, etc., is covered with a quartz cover 5, and the substrate 6 is mounted on a substrate holder 7 made of quartz to be heated by the SiC heater 3 via the quartz cover 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate manipulator for heating a substrate, which is used in a molecular beam epitaxial apparatus for forming a semiconductor thin film in a vacuum and a vapor phase growth apparatus.

[0002]

2. Description of the Related Art As a substrate manipulator used in a semiconductor thin film forming apparatus for forming a semiconductor thin film in a vacuum, for example, JP-A-5-275679 and JP-A-5-27534 are known.
There is 0 etc. Conventionally, as shown in FIG. 3, a heating source for heating the wafer 16, that is, a heater 17 is arranged on the substrate,
Generally, the method of heating the substrate by radiation is adopted.

[0003]

However, in the above-mentioned apparatus, since the metal part having a high temperature can be directly seen from the substrate, the heating source (heater) having a high temperature and the metal part constituting the heating source form a heavy metal (for example, Fe). , Ni, Cr, Cu
Etc.) diffuses and contaminates the substrate.

For this reason, the quality of the semiconductor thin film formed on the substrate has been remarkably deteriorated.

[0005]

In order to solve the above-mentioned problems, a heating source (heater) facing the substrate and a portion heated to a high temperature by the heating source are covered with quartz so as not to be directly seen from the substrate. Further, the present invention has invented a substrate manipulator in which a heater as a heating source is made of SiC and a substrate holder for holding a substrate is made of quartz to reduce heavy metal contamination.

[0006]

In the substrate manipulator according to the present invention, since the heating source (heater) and the portion heated to a high temperature by the heating source are covered with quartz, diffusion of heavy metal from the heated metal portion can be prevented by the coated quartz. Therefore, it is possible to prevent the heavy metal from contaminating the substrate. Also, the heater is S
Since iC and the substrate holder that holds the substrate are made of quartz, it is possible to prevent heavy metal contamination of the substrate.

Since heavy metal contamination of the substrate can be reduced as described above, a good quality semiconductor thin film can be formed.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an embodiment in which the substrate manipulator of the present invention is applied to a molecular beam epitaxial device. Several molecular beam sources 2 are arranged below the vacuum layer 1. There is a substrate manipulator on the upper part, and the SiC heater 3 and the heating part 4 holding the heater 3 are covered with a quartz cover 5. The cover 5 is fixed by a pin to prevent thermal stress. The substrate 6 is mounted on a substrate holder 7 made of quartz.

The substrate 6 is heated by the SiC heater 3 through the quartz cover 5, and the substrate 6 rotates. In this state, a molecular beam is irradiated from the molecular beam source 2 below to form a semiconductor thin film on the substrate 6.

Next, details of the substrate manipulator heating portion will be described with reference to FIG. A substrate holder 7 made of quartz is held by four columns 8 and a substrate 6 is mounted in the center. The substrate holder 7 has a structure that rotates and moves up and down.
On the other hand, in the heating section, there are several heat shield plates 9 above the SiC heater 3 and they are fixed to the alumina heat insulating plate 10. This heat insulating plate 10 is made of a metal plate 12 via a spacer 11.
The heating unit is held by the holder 13 as a whole. The entire heating portion such as the SiC heater 3 and the heat shield plate 9 is covered with a quartz cover 5. The cover 5 is fixed by a structure in which it is hooked by three pins 14 on the side surface of the plate 12, and the cover 5 can be removed. This fixing method prevents thermal stress on the quartz cover 5. The central line is a thermocouple 15 for measuring temperature.

When the SiC heater 3 is heated with the above-mentioned structure, the metal parts of the heating part such as the heat shield plate 9 are heated to a high temperature due to conduction and radiation, but the quartz cover 5 covers the entire heating part. Therefore, the high temperature metal parts cannot be seen directly from the substrate. Therefore, the cover 5 can prevent the diffusion of the high temperature metal component to the substrate, and the heavy metal contamination can be reduced. Further, since the heater is SiC and the substrate holder 7 is quartz, heavy metal contamination can be prevented. As a result, a good-quality semiconductor thin film with few impurities can be formed on the substrate.

[0012]

EFFECTS OF THE INVENTION According to the present invention, the heating source and the entire portion heated to a high temperature by the heating source are covered with quartz so that they are not directly visible from the substrate, thereby greatly reducing the contamination of the substrate with heavy metals. You can As a result, the semiconductor thin film formed on the substrate can be of good quality.

[0013]

[Brief description of drawings]

FIG. 1 is a schematic view in which a substrate manipulator according to the present invention is applied to a molecular beam epitaxial device.

FIG. 2 is a detailed cross-sectional view of the substrate manipulator shown in FIG.

FIG. 3 is a diagram of a conventional substrate manipulator.

[Explanation of symbols] 1 ... vacuum chamber, 2 ... molecular beam source, 3 ... SiC heater, 4 ...
..Heating part, 5 ... Cover, 6 ... Substrate, 7 ... Substrate holder, 8 ... Post, 9 ... Thermal shield plate, 10 ... Thermal insulating plate, 1
1 ... Spacer, 12 ... Plate, 13 ... Holder, 14 ... Pin, 15 ... Thermocouple, 16 ... Wafer, 17 ... Heater.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Eiichi Murakami 1-280, Higashi Koikekubo, Kokubunji, Tokyo Inside the Central Research Laboratory, Hitachi, Ltd.

Claims (4)

[Claims] 1. In a substrate manipulator for heating a substrate of an apparatus for forming a semiconductor thin film in a vacuum, a heating source facing the substrate and a portion heated to a high temperature are covered with quartz to reduce heavy metal contamination on the substrate. A substrate manipulator characterized in that 2. The substrate manipulator according to claim 1, wherein the heating source is made of SiC (silicon carbide). 3. The substrate manipulator according to claim 1, wherein the substrate holder for holding the substrate is made of quartz. 4. The substrate manipulator according to claim 1, wherein the quartz fixing method described above has a structure in which a fixing pin is hooked.