JPH0124536B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thin film production device, and particularly to a thin film production device using glow discharge.

As is well known, the formation of thin films by glow discharge is
Glow discharge is performed in a low-pressure gas, thereby decomposing gas molecules and depositing them on the surface of the substrate. Conventionally, this type of device uses a pair of parallel plate electrodes and attaches a substrate to one of the electrodes, or uses a parallel plate electrode and a grid electrode, and places the substrate behind the grid electrode. A device that generates a glow discharge between each electrode was used.

However, according to the former configuration, since the substrate is attached to the electrodes, the substrate is exposed to the plasma generated between the electrodes, so there is a risk that high-energy particles will collide and damage the produced film. .
In this respect, according to the latter configuration, since the substrate is located behind the grid electrode, there is less damage to the film due to collisions with high-energy particles, but on the other hand, the amount of film attached to the substrate and therefore the film thickness can be controlled. This becomes difficult.

It is an object of the present invention to avoid the incidence of high-energy particles and to enable control of the energy of charged particles incident on a substrate, thereby enabling control of film characteristics.

Embodiments of the invention will be described with reference to the drawings. 1 is a vacuum chamber, which is evacuated by a vacuum pump or the like via vacuum valve 2 (e.g., vacuum degree of about 10 ^-6 Torr)
be done. A gas corresponding to the film to be produced is supplied into the vacuum chamber 1 through a gas pipe 3 through an adjustment valve 4 that adjusts the gas flow rate. For example, Si
When a film is to be produced, a gas such as SiH ₄ is supplied. Reference numeral 5 designates a thin film adherend, such as a substrate for a semiconductor device, on the surface of which a film is to be adhered, and is supported by a substrate support 6. Reference numeral 7 designates a heater for heating the substrate 5.

Reference numerals 8 and 9 denote electrodes for glow discharge, and a power source (in the illustrated example, a DC power source is used, but a high frequency power source may be used) 10 is connected between the two electrodes for generating glow discharge. In the illustrated example, a Rogowski-type (including approximate Rogowski-type; the same applies hereinafter) electrode suitable for forming an equal electric field is used as one of the electrodes 8 and 9. This type of electrode has a structure with an appropriate roundness to avoid electric field concentration in the peripheral area. A Rogowski type electrode is used as the electrode 8 serving as an anode. the other electrode 9
is said to be grid-like. This is to make it easier for charged particles ionized by the plasma to fly toward the substrate 5.

A bias electrode 11 is provided between the substrate 5 and the electrode 9.
is placed. The electrode 11 has a grid shape, and the charged particles directed toward the substrate 5 are controlled by the potential applied thereto. For example, if a large amount of charged particles (for example, positive ions) are to be incident on the substrate 5, a negative potential may be applied, and if it is desired to reduce the amount of incident, a zero or positive potential may be applied.

In the above configuration, the power source 1 is connected between both electrodes 8 and 9.
When a voltage of 0 is applied, glow discharge occurs and plasma is generated. As a result, the gas supplied through the gas pipe 3 is decomposed and ionized (for example, into positive ions). At this time, the decomposed and ionized gas passes through the grid of the electrode 9 to which a negative voltage is applied, and is deposited as a film on the surface of the substrate 5 located behind it. In this case, since there is no substrate on the electrode, the produced film is not exposed to high-energy particles generated by the discharge and is therefore not damaged, resulting in a high-quality film. Become so. Furthermore, since the bias electrode 11 is disposed between the electrode 9 and the substrate, it is possible to control the incidence of charged particles, which play an important role in film formation, on the substrate 5, thereby forming a film with desired properties. will be able to generate.

In addition, in this example, a Rogowski-type electrode is used as one electrode, so a more uniform electric field can be obtained compared to the case where a normal parallel plate electrode is used. The plasma can be made uniform and a homogeneous film can be produced. In this case, since a concentrated electric field is not generated, substances forming the electrodes are not ejected from the electrodes due to collisions of ions, electrons, etc., and the substances that form the electrodes do not enter the membrane.

Furthermore, if the substrate 5 is provided on top as shown in the figure, even if the melt from the electrode falls, it will not enter the membrane, which is convenient.

As detailed above, according to the present invention, when gas is decomposed by glow discharge to form a film on a substrate, it is possible to avoid the incidence of high-energy particles, thereby making it possible to produce a high-quality film. Since a bias electrode is used, it is possible to control the film characteristics, which is advantageous.

[Brief explanation of drawings]

The figure is a sectional view showing an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Vacuum chamber, 3... Gas pipe, 5... Thin film adherend, 8... Rogowski type electrode, 10... Power supply,
11...Electrode for bias.

Claims (1)

[Claims] 1 A pair of electrodes for generating plasma by glow discharge, one of which is a lattice-shaped electrode, a thin film adherend is arranged behind the lattice-shaped electrode, and the lattice-shaped electrode and the thin film adherend A thin film generation device consisting of a bias grid-shaped electrode installed between the