JPH02110919A - Filming device - Google Patents

Abstract

PURPOSE:To manufacture the title filming device in high deposition ratio capable of moderately irradiating a substrate with ion at low pressure restricting mutual reaction of active seeds by a method wherein targets are formed of bar type target pieces while plasma control coils to converge plasma are arranged on the peripheral part outside the plasma route and so forth. CONSTITUTION:A target holder 17 and a substrate holder 8 opposite thereto are provided in vacuum vessels 1, 2; targets 19 are arranged on the target holder 17; a substrate to be filmed is arranged on the substrate holder 8 and simultaneously plasma is produced from the targets 19 to film the substrate 10. In such a filming device, the targets 19 formed of target pieces 20a-20c, a plasma chamber 1a and a filming chamber 2a are formed respectively in the vacuum vessels 1, 2 while plasma control coils 12-14 to converge the plasma are arranged on the peripheral position of the plasma chamber 1a and the filming chamber 2a.

Description

[Detailed description of the invention] A. Industrial application field The present invention relates to a film forming apparatus for semiconductor elements.

B8 Summary of the Invention The present invention provides a film forming apparatus for forming a film on a substrate by generating plasma between a target and a substrate, in which the target is formed of a rod-shaped target piece, and plasma is generated from the target piece. By providing a plasma control coil for controlling plasma, a film forming apparatus with excellent film forming characteristics can be obtained.

C1 Prior Art Conventionally, amonphasic semiconductors such as a-3i, a-SiC, and a-9iG+2 used in solar cells, etc., have been produced by a capacitively coupled RFPCVD method (radio frequency plasma chemical vapor deposition method).

D8 Problems to be solved by the invention The capacitively coupled RFPCVD method requires relatively high pressure (0°5~
Since this process is carried out at several Torr), the mean free path of the gas particles is short, causing large ion damage to the reciprocal core of active species in the gas phase and to the substrate, which is an obstacle to producing high-quality films.

Especially in a-9i, S i H, / CH4 = 1 /
Carbon dopant ffi (C introduction amount) into the film at a gas ratio of l
is about several percent (5 to 8%) no matter what. This makes it impossible to dramatically improve the characteristics. Also, if one type of C is changed to C, H, etc., the amount of C introduced increases, or -C,! There were many problems in which -15 groups entered the film and deteriorated the film quality.

The present invention has been made in view of two problems, and its purpose is to generate plasma by sputtering, which enables low-pressure film formation, and to solve the drawbacks of sputtering. It has a high deposition rate by solving the low deposition rate with the increasing effect of Targetera's l-surface bond, suppressing the interaction of active species under low pressure, and moderate ion irradiation to the substrate. The object of the present invention is to provide a film forming apparatus that can perform the following steps.

81 Means for Solving the Problems In order to achieve the above object, the present invention provides a target holder electrode and a substrate holder facing the target holder electrode in a vacuum container, and a target is disposed on the target holder electrode. , in a film forming apparatus in which a substrate to be film-formed is disposed in the substrate holder and a film is formed on the substrate by generating plasma from the target, the target is formed by a rod-shaped target piece;
A film forming apparatus is constructed by forming a plasma chamber and a film forming chamber in an nN vacuum chamber, and disposing a plasma control coil to converge the plasma on the outer periphery of the plasma path in relation to the plasma chamber and the film forming chamber.

Further, the target is constituted by an electrode rod, a target holder electrode connected to the electrode rod and arranged in the plasma chamber, and a plurality of rod-shaped target pieces attached to the target holder electrode.

19 Effects [1] The effective sputtering area is increased using a target with a rad, the gas plasma is controlled by the Helmholtz magnetic field effect, and the gas plasma is transported to the vicinity of the weir plate, and at the same time, the source gas is separated by the plasma, and the desired molecules are The inserted film is transferred to the substrate-L.
to be generated.

G. Embodiment An embodiment of the present invention will be described below with reference to FIGS. 1 to 1.

FIG. 1 is a schematic configuration diagram of a film forming apparatus according to an embodiment of the present invention, where l is a first container forming a plasma chamber (sputter source chamber) la, and this first container l is a The bottom is formed into a cylindrical shape. 2 is a film forming chamber 2 connected to the first container 1;
3 is an exhaust port, 4a is a first mass flow controller (MFC) that controls the flow rate of H gas, and communicates with the inside of the plasma chamber la through a first cock 5a. ing. 4b is a second cock 5 which controls the flow rate of the SiH4/H2 mixed gas;
It communicates with the inside of the film forming chamber 2a via b.

4C is a mass flow controller that controls the flow rate of the mixed gas of Cx Hy/H2, which is supplied to the film forming chamber 2a via the third cock 5C.
It communicates with 6 is a high frequency power supply (R-1; "power supply").

A substrate holder 8 is inserted into the film forming chamber 2a of the second container 2 via a bellows 7, and a heater 9 is installed in the substrate holder 8.
A substrate 10 on which a film is to be formed is also provided. A plasma rectifying plate 11 is arranged in the plasma chamber la of the first container l, and a first plasma control coil 12 and a second plasma control coil 13 are wound around the outer periphery of the first container l. At the same time, a third plasma control coil 14 is wound around the outer periphery of the second container 2.

A target holder 16 is disposed at the bottom of the first container I with an insulating member 15 in between. The target holder 16 consists of an electrode rod 17 and a target holder electrode 18, and the target holder electrode 18 has a target portion 19.
is installed.

As shown in FIGS. 2 and 3, the target portion 19 includes cylindrical target pieces 20a to 20a made of graphite material disposed on the same circumference in the target holder electrode 18.
20d, these target pieces 20a
20d are attached to the target holder electrode 18 by threaded portions 21, respectively.

In the film forming apparatus having the above configuration, hydrogen gas is introduced into the plasma chamber 1a which serves both as source generation and plasma generation using the introduced gas, and is ignited by high frequency power to generate hydrogen plasma. As a result, a graphite target is sputtered, and a large amount of CHx is instantaneously produced in one plasma.
Activated species are generated, and high-frequency power creates a constant mixing ratio, resulting in equilibrium.

In this state, there is no difference from normal sputtering, and the plasma diffuses toward the wall and becomes less dense. Therefore, the first plasma chamber was installed outside the plasma chamber 1a. By passing an alternating high frequency current through the second plasma control coil 12, 13 and controlling the current so that the target electrode diameter is approximately 70% of the target electrode diameter, a large amount of plasma can be generated densely and stably. . The generated plasma is drawn out toward the grounded substrate holder 8. At this time, the first. The plasma concentrated by the second plasma control coil 12, 13 is spread out.

In the film forming chamber 2a, a current (
It serves to collect the plasma spread by flowing AC) into the base [10], and controls m of the plasma by controlling the current of the second plasma control coil 13. S i H4 gas is introduced into the place where the plasma is controlled in this way, and 5it (4) is dissociated by the Ht plasma.
i I-1x species mix near the substrate, and CHx has higher energy, so SiC containing a large amount of C in the film
A film can be produced.

Examples will be shown regarding amorphous SiC produced as described above.

As shown in FIG. 1, a substrate 10 is set on a substrate holder 8 in a film forming chamber 2a and maintained at 300°C. After the base pressure is sufficiently evacuated to below lo' Torr (I 0-5 Pa), the flow rate is controlled by the first mass flow controller 4a to flow 503 CCM of hydrogen (Ht). In this state, the pressure inside the plasma chamber 1a is set to 0.2Torr (2,
2XIO-3Tor immediately after ignition at 65x 10Pa)
r (2,66XIO-'Pa). A high frequency JIKW is introduced to generate hydrogen plasma, sputtering the target portion 19, and introducing CHX species into the hydrogen plasma. At the same time, the first. Second plasma control coil 1
2.13, the plasma is concentrated to about 70% at about 10 to 2 OA.

Next, 1 l of SiH+ diluted with 30% H7 was added to the film forming chamber 2a.
OOSCCM did not flow. 5i) (2X] (I3'r
orr (2,66X10-'Pa).

At the same time, a current of 10 to 2
OA flows. By automatically reducing the current of the second plasma control coil 13 to about 1 to 5 A while monitoring the plasma state, an appropriate plasma state can be obtained on the substrate IO. The film-forming speed and E S CA (Elec
tron 5pectrosCopy For Che
Figure 4 shows the values of 0 in the film determined by mical analysis (X-ray photoelectron analysis).

The film forming apparatus of the above embodiment has the following advantages.

(1) Since the four cylindrical target pieces 20a to 20d are provided on the target holder electrode 18, the target area can be increased to about four times that of a flat target, and the four pieces are integrated by plasma generation. In order to create a plasma bulk, a large amount of CHx active species can be created.

(2) Since the pressure is on the order of 10-"I"orr, RF
It is possible to dramatically lengthen the mean free path compared to PCVD. This makes it possible to eliminate mutual reactions in the gas phase, making it possible to produce a high-quality film.

(3) Since the C source is obtained by sputtering, the kinetic energy of the C source is higher than that of the 5illx species, and for this reason, the conventionally said RFI) C in the case of CV D
There is no place where the amount of introduction is low.

(4) Plasma transport can be performed by the Helmholtz effect using three plasma control coils, and by controlling the coil current, the plasma density 11 can be maintained at a high level and stabilized even under low pressure.

1-1 Effects of the Invention The present invention is as described above, using a target that increases the effective sputtering area, transporting gas plasma to the vicinity of the substrate while controlling it by the Helmholtz magnetic field effect, and separating the source gas at the same time. By doing so, it is possible to produce a high-performance film.

[Brief explanation of the drawing]

The drawings relate to embodiments of the present invention, and FIG. 1 is a schematic configuration diagram of a film forming apparatus according to an embodiment of the present invention, FIG. 2 is a front view of a target section, and FIG. 3 is a side view of the target section. 4
The figure is a characteristic diagram of an example. I...first container, Ia...plasma chamber, 2...
Second container, 2a... Film forming chamber, 8... Substrate holder IO... Substrate, 12... First plasma control coil, I2... Second plasma control coil, 14...・
Third plasma control coil, 16...Target boulder-17/target holder electrode, 18...Electrode rod, I9...Target portion, 20a-20d...Target piece. Figure 4: R, F, power (W) Figure 2: Tarp area 211 B1 Figure 3: Turf's garden

Claims (2)

[Claims] (1) A target holder electrode and a substrate holder are provided in a vacuum container facing the target holder electrode, a target is provided on the target holder electrode, a substrate to be deposited is placed on the substrate holder, and In the film forming apparatus that generates plasma from the target to form a film on the substrate, the target is formed by a bar-shaped target piece, a plasma chamber and a film forming chamber are formed in the vacuum container, and the plasma chamber and the film forming chamber are formed in the vacuum chamber. 1. A film forming apparatus characterized in that a plasma control coil is disposed in a film forming chamber to converge the plasma at an outer peripheral portion of the path of the plasma. (2) The target is composed of an electrode rod, a target holder electrode connected to the electrode rod and arranged in the plasma chamber, and a plurality of rod-shaped target pieces attached to the target holder electrode. The film forming apparatus according to claim 1, wherein: