JP2828708B2 - Vapor phase growth equipment - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a vapor phase growth apparatus used for the purpose of obtaining a semiconductor thin film by a vapor phase growth method, and in particular, relates to the film thickness and electrical characteristics of the thin film. The present invention relates to a vapor phase growth apparatus suitable for achieving high uniformity.

[Conventional technology]

Not only elemental semiconductor such as Si, but also GaAs, AlGaAs, or InP
Vapor Phase Epitaxy (VPE) is known as one method for growing a group III-V compound semiconductor thin film. In this VPE method, raw materials for growing a thin film, molecular species involved in the growth, and impurities intentionally added to obtain desired electrical characteristics, so-called dopants, are also in a gaseous (gas) state. The thin film is introduced near the substrate, which is a deposit. As described above, one feature of the VPE method is that a chemical species involved in the growth of a thin film is introduced in a gaseous state near the substrate, but on the other hand, the film thickness and the electrical characteristics are uniformed. For this purpose, it is necessary to supply these gas species to the substrate as uniformly as possible. For this reason, conventionally, for example, a jig such as a nozzle is provided near the base in order to uniformly supply these gas species to the base.

[Problems to be solved by the invention]

However, as described above, even when a nozzle or the like is provided, for example, in the actual operation of growing a thin film, when it becomes necessary to change the total amount of gas supplied onto the substrate as a deposit. In some cases, in order to obtain uniform characteristics, it is sometimes necessary to change a nozzle or the like having a shape corresponding thereto. Further, the temperature at which the growth of the thin film is performed is, for example,
Also in the case of changing the desired electrical characteristics to obtain the desired electrical characteristics, in conjunction with changing the temperature, in the vicinity of the substrate, taking into account phenomena such as volume expansion of the supplied gas species or thermal diffusion,
Complicated measures have been taken, such as newly providing a nozzle or the like having a shape suitable for that, or changing the distance between the nozzle and the base.

For this reason, conventionally, in order to obtain a thin film having uniform characteristics in response to changes in growth conditions, frequent and complicated operations such as repeatedly performing operations of attaching and detaching nozzles and the like one by one according to the conditions have been required. Was. In carrying out this work, the reaction system must be temporarily decomposed, so that the reaction system is exposed to the air, and the subsequent thin film growth, especially when the film contains oxidizable elements. In the case of growing a thin film to be added or added, it enters into the reaction system due to the above-mentioned decomposition operation, and causes a serious obstacle to stable growth of the film quality due to the influence of adsorbed oxygen, water and the like. There was a problem.

[Means for solving the problem]

The present inventors have avoided the frequent and complicated work involved in the desorption of the nozzle and the like, as seen in the conventional example, and thus, the invasion of outside air into the reaction system caused by the desorption device of the nozzle and the like, and contamination, etc. As a result of intensive studies to provide a method for suppressing the occurrence of the above problem and contributing to the stability of the thin film containing the easily oxidizable element, a mechanism is provided for changing the position of the nozzle with respect to the substrate by operating the nozzle from outside the reaction system. As a result, the inventors have found that the disadvantages associated with the conventional method as described above can be eliminated, and have led to the present invention.

That is, the present invention provides a gas phase comprising a jig for a nozzle provided for the purpose of supplying a source gas for deposit growth in a reaction vessel provided for carrying out growth in the vicinity of a deposit. A vapor phase growth apparatus characterized in that the growth apparatus is provided with a mechanism for freely changing and adjusting the distance (position) of the nozzle with respect to the deposit from outside the reaction vessel. .

〔Example〕

Hereinafter, a specific description will be given based on an embodiment according to the present invention.

FIG. 1 shows a mechanism for changing the nozzle position from outside the reaction system according to the present invention. In the figure, 101 is a substrate on which a desired thin film is deposited, and 102 is a substrate 1
A nozzle for supplying a reaction gas as a raw material to 01. The nozzle 102 is supported by a support 103. The support 103 has a flange 104 attached to the reaction vessel 110.
A male screw portion 106 that penetrates through to the outside of the reaction system 105 is connected. The male screw portion 106 operates in conjunction with the female screw portion 107 connected to the flange 104. The female screw portion 107 is fixed to the flange 104 in a slidable manner via a slide fixing jig 111 attached to the flange 104. The male screw portion 106 is formed hollow, and a reaction gas pipe 112 for supplying a reaction gas penetrates the inside, and one end is connected to the nozzle 102 and the other end is connected to a gas supply system (not shown). Have been. Reference numeral 108 denotes a bellows, one end of which is connected to the support 103 and the other end of which is connected to the flange 104 to prevent the inflow of raw material gases into the male screw portion 106, and thus the raw material to the outside of the reaction system 105. It has the role of preventing the leakage of gases and, conversely, the intrusion of outside air into the reaction system 105.

In order to change the distance (position) of the nozzle 102 with respect to the base 101 by the above-described configuration, the male screw portion 107 is rotated in a desired direction, and the male screw portion 106 is moved upward and downward. For example, the distance of the nozzle 102 can be easily and quickly changed from outside the reaction system 105.

Further, in order to grasp the position of the nozzle 102 with respect to the base 101, for example, if a scale 109 or the like indicating the positional relationship is provided in a part of the flange portion 104, the positional relationship can be easily recognized.

[Action]

According to the present invention, the distance between the nozzle and the substrate can be freely changed from the outside without breaking the airtightness of the reaction system. Therefore, for example, even when it is necessary to change the flow rate of the gas supplied to the reaction system during growth,
Since the distance between the nozzle and the base can be changed quickly and easily, there is an advantage that the electrical characteristics of the obtained thin film can be easily made uniform.

〔effect〕

As described above, according to the present invention, there is an advantage that the position of the nozzle with respect to the base can be easily and easily changed without any complicated operation and without the need to decompose the reaction system. Therefore, as seen in the conventional example, due to the release of the reaction system to the outside air due to the change in the position of the nozzle,
This has a practical effect that the stable growth of the thin film is not impaired.

Furthermore, if the mechanism according to the present invention is used, the positional relationship between the nozzle and the substrate can be rapidly changed, so that during the growth of a thin film, it is necessary to rapidly change the source gases in the middle of the growth. In such a case, it is possible to correct the positional relationship in order to obtain a thin film having uniform characteristics promptly in response thereto, and thus there are many things that contribute to the growth of a highly uniform thin film.

In the present embodiment, the position of the nozzle is variable by converting the rotational movement of the male screw and the female screw into a vertical movement.
The effect of the present invention can be exerted not only in the case of such a power transmission mechanism but also in the case of using a mechanism for varying the positional relationship of the nozzle from the outside of the reaction system only by a linear motion, for example.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 schematically shows a mechanism for changing the position of a nozzle constructed in accordance with the present invention with respect to a substrate. In FIG. 1, reference numeral 101 denotes a thin film being deposited. The base, 102 is the nozzle, 103 is the support for the nozzle, 104 is the flange, 105 is the reaction system, 106 is the male thread, 107 is the female thread, 108 is the bellows, and 109 is the scale. Are respectively shown.

────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Takashi Udagawa 1505 Shimokagemori, Chichibu City, Saitama Prefecture Showa Denko Chichibu Plant (56) References JP-A-63-164308 (JP, A) JP-A-61- 208222 (JP, A) Fully open 1983-158438 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01L 21/205 H01L 21/31 C23C 16/44 C30B 25/14 C30B 25/16

Claims (1)

(57) [Claims] 1. A gas phase growth apparatus comprising a nozzle provided in the vicinity of a deposition object for supplying a source gas for deposit growth in the reaction vessel, and attached to the reaction container. A hollow male screw is provided through the flange, and a female screw meshing with the male screw is slidably attached to the flange, and a nozzle is installed at a lower end of the male screw via a support. And a mechanism for changing and adjusting the distance of said nozzle to said deposit from outside said reaction vessel using a structure comprising: