JPS6240386A - Ecr plasma treatment device - Google Patents

Abstract

PURPOSE:To improve the film thickness by a bias effect by connecting a DC power source, etc., to a substrate electrode to control the ion sheath of the ions which are generated by an ECR type ion source and plunge into a substrate thereby suppressing the ion energy plunging into the substrate. CONSTITUTION:The ions in plasma 6 diffused from a working chamber 3 are bombarded to the substrate 9 and the thin film on the surface of the substrate 9 is subjected to, for example, etching. The DC power source 10 or RF power source 11 is connected to the substrate electrode 7 and is so constructed that said power source is controlled by the bias voltage to be applied to the substrate electrode 7. The damage to the substrate 9 is diminished if the energy plunging into the substrate 9 is decreased by changing, for example, the bias voltage by the DC power source 10 or RF source 11. The changes of etching speed and step coverage are also made possible.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention uses an ECR type ion source, that is, an electron cyclotron resonance type ion source, which generates ions by introducing microwaves into a resonant magnetic field. Ion beam etching that generates plasma, Plasma C
The present invention relates to plasma processing equipment such as VD equipment.

(Prior Art) As a conventional plasma processing apparatus using an ECR type squid ion source, those shown in FIGS. 1 and 2 are known. The one shown in the first diagram has a working chamber in which an electron cyclotron resonance magnetic field is formed by a magnet a provided around the working chamber.
It is equipped with an ion source that introduces microwaves through an introduction tube C and a ceramic chamber d to generate a plasma e in the action chamber, and the ions in the plasma are transferred to an extraction electrode f.
is extracted as ion beam 1 by the potential applied to
It collides with the substrate provided on the substrate electrode Q and is used for etching or film formation.

In addition, in the case shown in the second diagram, microwaves are introduced into a working chamber in which an electron cyclotron resonance magnetic field is formed by a magnet a through an introduction tube C and a ceramic window d, and a plasma e is generated in the working chamber. Having an ion source is the first
This is similar to the one shown in the first diagram, except that the substrate electrode Q is connected to the ground, and the ions in the plasma that have diffused from the working chamber are made to collide with the substrate by the ground potential of the substrate electrode q. differ. Note that the reactive gas introduction path for etching or film formation is omitted in FIGS. 1 and 2.

(Problems to be Solved by the Invention) In the case of the one shown in the first figure, if the energy applied to the extraction electrode f is less than 300V, the ion beam i cannot be extracted to the substrate, so a relatively large amount of energy is applied. The acceleration energy has to be applied to the electrode f, and therefore the acceleration energy becomes large, damaging the substrate and making it impossible to form a fine pattern on the substrate.

In addition, the plasma e shown in the second figure can only be generated under certain conditions, and unless the distance between the ion source and the substrate is changed or the working pressure is changed, substrate processing conditions such as etching rate, film formation rate, step coverage, etc. can be changed. There is a disadvantage that it is not possible to form a fine pattern on the substrate by changing the distance or pressure.

The present invention forms fine patterns or films by arbitrarily controlling the plasma ions diffused from the ECR ion source while keeping the plasma generation conditions of the ECR ion source constant and changing the conditions for collision with the substrate. The purpose is to improve the situation.

(Means for Solving the Problems) In the present invention, plasma is generated by an ECR type ion source, and ions in the plasma are made to collide with a substrate provided on a substrate electrode. The above object was achieved by connecting the electrode to a DC or other power source that controls the ion sheath in front of the electrode to apply a bias voltage.

(Function) The plasma generated by the ECR type ion source diffuses in the direction of the substrate electrode, and when the ions in the plasma collide with the substrate provided on the substrate electrode, they are subjected to etching treatment or A part of the material deposited by ECR plasma CVD is reverse sputtered to perform the film deposition process. This action is similar to that of conventional plasma processing equipment, but in the present invention, the substrate electrode is supplied with a DC power source or a
3 Since a bias voltage is applied by the RF power supply of QHH7, the ion sheath in front of the substrate electrode can be adjusted arbitrarily by adjusting the bias voltage without the aid of the beam extraction electrode f shown in FIG. The energy to attract ions in the plasma can be adjusted arbitrarily.

When a thin film is formed on the surface of the substrate, if the bias voltage is controlled to reduce the ion sheath, the collision energy of ions against the substrate will also be reduced, and the step coverage and refractive index of the thin film will be controlled, thereby controlling the film quality. I can do it.

(Embodiment) An embodiment of the present invention will be explained with reference to FIG.
) consists of an action chamber (3) in which an electron cyclotron resonance magnetic field is formed by a surrounding magnet (2), and an introduction pipe (5) that guides microwaves into the action chamber (3) through a ceramic window (4). When microwaves are introduced into the working chamber (3), a plasma (6) is generated inside the working chamber (3). (1) is a substrate electrode installed in a vacuum processing chamber (8) connected to the action chamber (3);
is attached to the front surface of the substrate electrode (7) and is connected to the action chamber (3).
) is the substrate facing the opening.

The substrate (9) is filled with plasma (
6) is collided with the thin film on the surface of the substrate (9), for example, to etch the thin film on the surface of the substrate (9).
RF frequency such as H2 to 30811Z to G or 50
Two power supplies were connected to control the bias voltage applied to the substrate electrode (1). Power supply (IO or al
For example, by changing the bias voltage of the ionic substrate (9)
By reducing the energy entering the etching process, damage to the substrate (9) can be reduced, and the etching speed and step coverage can be changed. It is easier and easier to control the etching speed etc. by changing the etching speed.
This is advantageous because uniform processing can be performed.

(Effects of the Invention) As described above, in the present invention, the ion sheath of ions generated in the ECR type ion source and entering the substrate is
Since the ion energy entering the substrate can be controlled by connecting a C power source, etc., controllability is good, and substrate processing conditions such as step coverage and etching speed during film formation can be easily changed. This effect can be expected to improve film quality, and etching also has the effect of forming fine patterns on a substrate.

[Brief explanation of drawings]

1 and 2 are explanatory diagrams of a conventional example, and FIG. 3 is a diagram illustrating an embodiment of the present invention. (1)...ECR type ion m (e)...Plasma (1)...Substrate electrode (9)...Substrate (10...DC power supply an...RF power supply Figure 2) Figure 3

Claims (1)

[Claims] In a device in which plasma is generated by an ECR type ion source and ions in the plasma collide with a substrate provided on a substrate electrode, a DC or other power source is provided to control the ion sheath in front of the substrate electrode. An ECR plasma processing apparatus characterized in that a bias voltage is applied by connecting the ECR plasma processing apparatus.