JP2776877B2 - Substrate holder - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molecular beam epitaxy apparatus or a similar type of substrate holder used in an ultra-high vacuum, and more particularly to a substrate holder suitable for a case where a conductive substance is adhered. It is about.

[Conventional technology]

The substrate holder contains lead wires for the substrate heater, thermocouples,
A beam monitoring lead wire or the like is provided. Conventionally, however, the lead wire has been covered with a fishbone-shaped insulator to add resilience to revolving motion.

This type of substrate holder is described in, for example, Takahashi, "Molecular Beam Epitaxy Technology", edited by the Industrial Research Council, and the like.

[Problems to be Solved by the Invention] The above-mentioned prior art discloses a material (for example, Ga, As, etc.) that evaporates from a molecular beam source to an insulating insulator covering a heater and a thermocouple lead wire built in a substrate holder. It is difficult to say that the protection is sufficiently protected against the adhesion, and there has been a problem that the adhesion sometimes goes into the insulating insulator and causes an electric short circuit.

An object of the present invention is to provide a highly reliable substrate holder that does not expose a lead wire to a space where an evaporant flies, and does not cause a short circuit for long-term use.

[Means for solving the problem]

The above object is achieved by making a supporting shaft hollow, and wiring a lead wire covered with an insulating insulator through the inside of the hollow shaft.

[Action]

In the MBE device, the substrate holder supports the substrate,
Exposure in the evaporant causes crystal growth, and it is inevitable that the evaporate adheres to the substrate holder. The present invention and the prior art are the same in that the mechanism including the bevel gear is covered with a cover so that no evaporant is attached to the cover.

According to the present invention, the lead wire is directly inserted into the hollow revolving shaft without putting out various lead wires out of the cover, the revolving shaft is used as a cover, and the boss 9 for supporting the revolving shaft is further provided. Since the lead wire is exposed to the space via the support plate 9a, the support plate 9a functions as a cover, and no evaporated matter adheres to the lead wire.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows an embodiment of the present invention, in which 1 is a room forming a part of a vacuum vessel and accommodating a power transmission mechanism, which is fixed to a growth chamber of a molecular beam epitaxy apparatus by a flange 1a. Lid 2
Is provided to facilitate the work in the room 1.

The port 3 is provided in a part of the lid 2 and the rotation introducing machine 4 is mounted. The vacuum side shaft 5 of the rotation introducing machine 4 is axially and elastically engaged with the extension shaft 6, and the extension shaft 6 is rotatably supported by bearings 7a and 7b at portions near respective ends.

A small bevel gear 8 is fixed to the other end of the extension shaft 6. On the other hand, a hollow shaft 11 is rotatably supported on bearings 10a, 10b provided on a boss 9 fixed to the room 1, and a hollow shaft 12 integrally formed or fixed to one end of the hollow shaft 11 by means such as bolts. And a large bevel gear 14 meshing with the small bevel gear 8 is rotatably supported via the bearings 13a and 13b. A pinion gear 15 is fixed to the other end of the hollow shaft 11, and a rack 16 meshing with the pinion gear 15 is guided by a bearing 18, and one end of the rack is connected to a shaft 20 by a pin 19, and is connected to a port 21. The bellows 22 is connected outside the vacuum chamber.

The shaft 20 is fixed to the bellows 22 by welding or the like, and one end is connected to an air cylinder (not shown) or the like.

In the part 24 in which the element parts are incorporated, the aforementioned small bevel gear,
Along with the bevel gears and bearings, a heater 25 for heating the substrate, an insulating member 26 for supporting the heater 25, and a heat shield plate 27 for shielding the heat of the heater 25 are supported by the supporting columns 28 of the insulator. The body strut 28 has a hollow shaft 1
It is pivoted to two. Also, a claw 32 for gripping the susceptor 31
And the outside is covered with covers 33 and 34.

FIG. 2 shows details of a method of connecting a lead wire of a heater for heating a substrate in FIG. 1. An insulating member 26 for supporting a heater 25 is provided on a post 28 of an insulator and a screw 37 with a cap 37. The electric power line 36 is connected to the insulating member 26 supporting the heater 25 on the side opposite to the mounting surface of the heater 25, and is inserted into a hole 39 formed in the center of the insulating support 28. Incorporate in

FIG. 3 shows a cross section AA of FIG.
Incorporates another insulator 38 into which a thermocouple for measuring the temperature of the substrate is inserted as an elliptical hole or an oval hole, and the insulator 38 insulates the electric power lines 36a and 36b. I try to do it. A thermocouple is incorporated in the small hole 40 in the insulator 38.

FIG. 4 relates to the mounting of a thermocouple 50 for measuring the temperature of the substrate. A small hole smaller than the outer diameter of the insulator 38 is formed at the tip of the cap 37, and the cap 37 is held by the insulator 38. By accommodating the thermosensitive part of the thermocouple 50 in the small hole, the temperature of the heater 25 is not directly detected by the thermocouple 50, and the susceptor 31 contacts the thermocouple 50 when the susceptor 31 is delivered. To prevent.

Next, a method of wiring the electric power line 36 and the thermocouple 50 of the heater 25 will be described.

As described with reference to FIGS. 2 to 4, the electric power line 36 and the thermocouple 50 of the heater 25 penetrating the support 28 of the insulator are provided with holes in the seat fixed to the hollow shaft 11 or fixed by means such as bolts. A hollow insulator 51 is incorporated, a hollow insulator 52 is penetrated inside the hollow shaft 11, the insulator 51 and a hole of the insulator 52 are taken out into the room 1, and the insulator 53 is installed in the room 1. Connected to the current introduction terminal 55 attached to the port 52.

Since the present invention is configured as described above, there is no case where evaporates during crystal growth reach various leads, and no evaporates adhere to the leads.

〔The invention's effect〕

ADVANTAGE OF THE INVENTION According to this invention, since the short circuit accident does not generate | occur | produce by evaporation substance adhering to a lead wire, the frequency of a vacuum break is significantly reduced, and there exists an effect that a device can be operated stably over a long period of time.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a substrate holder according to an embodiment of the present invention, FIG. 2 is a detailed cross-sectional view of a heater connecting portion of FIG. 1, and FIG.
FIG. 4 is a detailed cross-sectional view of the thermocouple mounting portion of FIG. 3, and FIG. 1 ... vacuum vessel, 9 ... boss, 9a ... boss support plate, 11
…… Hollow shaft, 25… Heater, 33,34 …… Cover, 50 ……
Thermocouple, 51 ... insulator, 52 ... insulator tube

──────────────────────────────────────────────────の Continued on the front page (58) Field surveyed (Int. Cl. ⁶ , DB name) C30B 23/00-25/22 H01L 21/203-21/205 H01L 21/31 C23C 14/00-16 / 56

Claims (1)

(57) [Claims] 1. A power transmission unit disposed in a crystal growth chamber of a molecular beam epitaxy apparatus and hermetically attached to a part of the crystal growth chamber, and transmitting power from the power transmission unit to the crystal growth chamber. A transmitting means, a revolving portion of the substrate connected to the transmitting portion, a substrate gripping means for holding a susceptor for holding the substrate provided in the revolving portion, a heater for heating the substrate, and a thermocouple for measuring the temperature. In the substrate holder comprising: a revolving portion of the substrate, a cover that covers the revolving portion, the substrate gripping means, the heater and the lead wire of the thermocouple, and prevents adhesion of evaporated substances during crystal growth processing, A substrate holder, wherein a revolving shaft of the transmission means is formed by a hollow shaft, and leads of the heater and the thermocouple are passed through the hollow shaft.