JPS59167013A - Plasma cvd equipment - Google Patents

Abstract

PURPOSE:To reduce the heat loss for substrate heating by a method wherein substrates are mounted on a tray and this tray is so constructed as to surround and contain one heat source from both sides in a vertical plane. CONSTITUTION:A substrate heater 5 fixed in a vacuum vessel is provided vertically. Substrates 7 on which films are formed are mounted on a tray 8. The tray 8 is hung surrounding both sides of the heater 5 so that the heat radiated from the heater 5 is kept in a space between the heater 5 and the tray 8. High frequency electrodes 4 are provided in parallel with an interval from each side of the tray 8, and plasma reaction is generated at both sides of the heater to form the prescribed films on the substrates 7. Because the substrates 7 and other items are provided vertically, even if undesirable reaction products adhered to the walls of the vessel and the like fall off, they are not deposited on the substrates 7.

Description

[Detailed Description of the Invention] 7@Ming is an E-plasma CVD method that utilizes high-frequency plasma reactions used to form thin films such as amorphous silicon films or silicon nitride films used in solar cells and sensors.
Regarding device n.

As this type of plasma CVD apparatus, one having the structure shown in FIG. 1 is known. The figure shows the cross-sectional structure of the device, and the true wall container l is evacuated to vacuum by the true wall exhaust device x2. After introducing a multi-material gas (for example, silane gas) into the gas-introducing pulp 3 to a predetermined pressure, a high-frequency power source 6 is connected between the high-frequency electric power &4 and a counter electrode 5 which also serves as a heater for heating the substrate.
By applying a high frequency electric field and causing a plasma reaction, a thin film (an amorphous silicon film in this case) can be formed on the tray 8 on which the substrate 7 is mounted. In this case, the substrate heating method is to install the tray in close contact with the heating heater 5 or in a state where it is separated for a certain period of time, and to control the desired temperature from the back surface of the substrate. However, according to this method, the surface area that effectively contributes to substrate heating with respect to the total surface area of the heater is less than 5°, and most of the heat emitted from the sb heat source is radiated as radiant heat, resulting in heat loss. Thermal efficiency is poor as °2i increases.Furthermore, the heat radiation situation is different between the central part of the heater where the tray is adjacent and the peripheral part which is the open end, and the temperature uniformity within the tray surface cannot be maintained. There are drawbacks.

'11 The present invention eliminates the above-mentioned drawbacks and improves the heating of the substrate.
It is an object of the present invention to provide a plasma CVD apparatus with low heat loss.

The purpose of this is to install a plate-shaped heating element that also serves as one electrode in a vacuum container, two opposing electrodes located at equal intervals from both sides of the heating element, and heating the spaces between the heating element and the opposing electrodes. This is achieved by having a thin film forming substrate support located close to the body, and the plate-like heating element, counter electrode and substrate support all being in a vertical plane.

Embodiments of the present invention will be described below with reference to the drawings. In each figure, common parts are given the same reference numerals.

In FIG. 2, the heater 5 for heating the substrate fixed to the vacuum container 1 is composed of a sheathed heater or a cast-in heater, and 14fillO for ships is for transferring the tray together with the carrier to another vacuum chamber. This itself is well known, and conveys the power from a motor to rollers using a chain or the like. High-frequency electrodes 4 are placed on both sides at a distance of 10 to 150 m from each tray.
are arranged in parallel, and after opening the gas introduction pulp inside the vacuum container 1 and adjusting the desired pressure within the range of 0.1 to 10 Torr,
By applying an fcw field generated from a high frequency power source 6 to the substrate heating heater 5 which also serves as a counter electrode, a plasma reaction is generated on both sides of the heater 5, and a desired film can be formed on the substrate 7 on the tray 8. . Here, since the substrates and the like are arranged vertically, measures are taken to prevent undesirable reaction products generated by the plasma reaction adhering to the walls of the container from falling and depositing on the substrates.

In order to further improve the thin film production ability, multiple rows of high frequency electrodes and substrate heaters can be arranged in parallel. Fig. 3 shows such an embodiment, and the difference from Fig. 2 is that the fixed heater tffi for heating the substrate is used.
51 and 52 can be arranged in two rows and linked together by a single pivoting device 10 to facilitate control of transfer.

By arranging the base@ in multiple layers in this way, the conventional method shown in Fig. 1 is improved! The substrate processing capacity can be dramatically increased by two times in the embodiment shown in FIG. 2 and four times in the embodiment shown in FIG.

Figure 4 is an application example of the embodiment shown in Figure 2, showing an apparatus for forming a thin film element having a multi-e structure (for example, an amorphous silicon photovoltaic element with a pin structure). FIG. The vacuum chambers 11-14 are separated by partition valves 21-25 and can be evacuated independently. Here, the first vacuum chamber 1] is a preheating chamber for the substrate, and the vacuum volume shown in FIG. The difference from a1 is the high frequency electrode 4.
In place of this, a heating heater 53 is installed at that position, thereby making it possible to shorten the substrate heating time. The vacuum chambers 12 to 14 are reaction chambers, and in cases where the incorporation of doping impurities into the i-layer becomes a problem, such as in the formation of the pin structure amorphous negative silicon element, each j ―
It is effective to separate the producing groups. First, after preheating in the preheating chamber 11, the carrier is transferred to the second vacuum chamber 12 using a carrier as shown in FIG. 2, where the transfer between the vacuum chambers is performed under the same vacuum pressure.

According to the present invention, a tray equipped with a board serving as a horizontal heating element surrounds and sandwiches a fixed heater heat source from both sides in a vertical plane, so that the in-plane temperature of the tray on both sides is uniform. In addition to reducing heat loss due to radiation, processing capacity and power are doubled by arranging substrates in multiple rows, greatly improving mass productivity. The effect is that an improvement is obtained.

[Brief explanation of the drawing]

Figure 1 is a side sectional view of a conventional amorphous silicon film production device.
FIG. 2 is a side sectional view of an amorphous silicon film production apparatus according to one embodiment of the present invention, FIG. 3 is a side sectional view of another embodiment of the present invention, and FIG. 4 is a horizontal sectional view of yet another embodiment. entrust DESCRIPTION OF SYMBOLS 1; Makabe container, 4... High frequency electrode, 5... Heater for substrate heating, 7... Substrate, 8... Tray,
11 to 14, 1 vacuum chamber.

Claims (1)

[Claims] 1) A plate-shaped heating element with one electrode in a vacuum container, two opposing electrodes located at equal intervals from both sides of the heating element, and a heating element in the space between the heating element and the opposing electrode. A plasma CVD device comprising a plate-shaped heating element, a pair of electrodes and a substrate support, all of which are arranged in a vertical plane.
Device.