JPH0810635B2 - Plasma processing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Outline] The present invention is directed to a plasma processing apparatus in an induction discharge type high frequency plasma apparatus or the like, in order to solve the problem of the conventional apparatus in which the plasma is contaminated by the spark plug sputtering. By igniting the plasma by utilizing the dielectric breakdown of the laser light, the plasma can be ignited without being contaminated, and the plasma can be uniformly generated.

[Industrial applications]

The present invention relates to a plasma processing apparatus, and more particularly to an induction discharge type high frequency plasma processing apparatus used in a plasma CVD apparatus or the like. Generally, in a plasma CVD apparatus, since a fine wafer is subjected to film formation processing, it is desirable that the inside of the chamber be kept clean without being contaminated.

[Conventional technology]

FIG. 2 shows a schematic view of an example of a plasma processing apparatus in a conventional induction discharge type high frequency plasma apparatus. Reference numeral 1 denotes a chamber in which gas is introduced and exhausted as is well known. Two
Is a high frequency generator and is attached to the outer periphery of the chamber 1. HF is a high frequency power supply. 3 is a spark plug,
For example, the upper surface side of the chamber 1 is attached so as to project into the chamber 1. Reference numeral 4 denotes a wafer, which is installed in the chamber 1.

Here, a high frequency is generated in the high frequency generator 2 by the high frequency power supply HF, and a spark is generated by the spark plug 3, whereby plasma ignition is performed in the chamber 1. Gas is introduced and exhausted in the chamber 1, and the wafer 4 is formed by plasma CVD as is well known.

[Problems to be solved by the invention]

In the conventional device, plasma ignition is performed by the spark plug 3
However, when the spark plug 3 wears due to aging, the metal particles of the spark plug 3 scatter and enter the plasma, which contaminates the plasma. In addition, since the spark plug 3 protrudes from the plasma generation point in the chamber 1, this has a problem that the plasma in the chamber 1 is not uniform.

[Means for solving problems]

A dielectric high-frequency plasma processing apparatus according to the present invention is a dielectric high-frequency plasma processing apparatus having a chamber having a gas inlet and a gas outlet and a high-frequency generator attached to the outer periphery of the chamber. A laser generator for condensing the laser light is provided, and a spark is generated by dielectric breakdown by the laser light in the condensing portion of the laser light to perform plasma ignition.

[Action]

Spark is generated by dielectric breakdown of the focused laser light, and plasma ignition is performed.

〔Example〕

FIG. 1 is a schematic view of an embodiment of the plasma processing apparatus for induction discharge type high frequency plasma according to the present invention. In FIG. 1, the same components as those in FIG. To do. In the figure, reference numeral 5 denotes a chamber, which is made of, for example, quartz glass or the like, and a window 6 made of quartz glass or general glass is provided above the chamber. Reference numeral 7 denotes a laser light generator which is configured to generate, for example, an excimer laser light 9 having a peak output of at least about 10 MW, and the laser light 9 is focused by a lens 8 and reaches the chamber 5 through a window 6. Has been done.

The laser light 9 of about 10 MW generated by the laser light generator 7 is focused by the lens 8 and reaches the chamber 5 through the window 6. In the chamber 5, dielectric breakdown occurs at the focal point of the laser light 9 and a spark (10) occurs. Plasma is ignited in the chamber 5 by the spark 10.

In this case, the plasma ignition is performed by the spark generated by the dielectric breakdown at the focal point of the laser beam 9, so that the plasma is not contaminated unlike the spark generated by the sputtering of the spark plug 3 of the conventional apparatus shown in FIG. Further, since there is no projecting portion in the plasma generating portion of the chamber 5 unlike the spark plug of the conventional apparatus shown in FIG. 2, an equipotential surface can be formed over a wide range and the uniformity of plasma can be maintained.

〔The invention's effect〕

According to the present invention, since the spark is generated by the dielectric breakdown of the laser light, plasma ignition can be performed without causing plasma contamination due to the scattering of metal particles of the spark plug as in the conventional device, and the window to the chamber is provided. Since it is not necessary to provide something like a spark plug in the chamber unlike the conventional device, the structure of the chamber can be simplified and the chamber can be configured in a small size. Since it does not have a protruding portion unlike the device, it has features such that an equipotential surface can be formed over a wide range and plasma uniformity can be maintained.

[Brief description of drawings]

FIG. 1 is a schematic view of an embodiment of the device of the present invention, and FIG. 2 is a schematic view of an example of a conventional device. In the figure, 2 is a high frequency generator, 4 is a wafer, 5 is a chamber, 6 is a window, 7 is a laser beam generator, 8 is a lens, 9 is a laser beam, and 10 is a spark.

Claims (1)

[Claims] 1. A dielectric high-frequency plasma processing apparatus having a chamber having a gas inlet and a gas outlet, and a high-frequency generator attached to the outer periphery of the chamber, wherein the laser generator concentrates laser light in the chamber. The dielectric high-frequency plasma processing apparatus is characterized in that a spark is generated by dielectric breakdown due to laser light in a laser light condensing portion to perform plasma ignition.