JPS6384028A - Processing apparatus using plasma - Google Patents

Abstract

PURPOSE:To conduct a uniform and high-speed plasma processing by providing a plurality of solenoid coils which have the respective central axes different from one another and parallel substantially to the central axis of a chamber, and by letting currents different in phase flow through the coils sequentially. CONSTITUTION:Solenoid coils 10 in a plural number of (n) (n >= 2) whose central axes do not accord with one another are disposed around a plasma chamber 5. Currents being different in phase are let to flow sequentially through the coils 10. Then a plasma generated between electrodes 1 and 4 is put in a straight or rotary motion by a magnetokinetic field generated by the coils 10 and maintained between the electrodes 1 and 4 for a long time. Thereby a uniform and high-speed plasma processing is effected over a wide area of a substrate 9.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a plasma processing device, which is a semiconductor processing device, which generates plasma by high-frequency discharge and enables uniform and high-speed plasma processing over a wide area. The present invention relates to a plasma processing apparatus.

[Conventional technology]

FIG. 4 is a schematic cross-sectional view showing a conventional plasma processing apparatus shown, for example, in P. 19B of "Fundamentals of Thin Film Creation" by Tatsuo Asamaki (Nikkan Kogyo Sha Series); electrode, (2) is a high-frequency power supply, (3) is a high-frequency matching device, +4+H counter electrode, (5) is a plasma chamberer, (
6) a shield plate, (7) a plasma, (8) an insulator, and (9) a substrate as a workpiece.

Next, the operation will be explained. In this device, a high frequency application electrode ill and a counter electrode (
4) between the high frequency power supply (2) and the high frequency matching box (3).
) Generate plasma (7) by applying a high frequency voltage via f, and utilize the chemical reaction and physical action of plasma (7),
Thin film formation, surface treatment, etching, etc. are performed on the substrate (9).

[Problem that the invention seeks to solve]

Since the configuration is more than that of the conventional plasma processing apparatus i, plasma (
7) occurs. The generated plasma (7) is transferred to the substrate (9
), thin film formation, surface treatment, etching, etc. are performed on the
A considerable part of the generated plasma (7) is located opposite the high frequency electrode fl+ i! The generated plasma (7
) is used effectively for plasma processing, and as a result, the plasma processing speed is low and plasma processing cannot be performed uniformly.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a plasma processing apparatus that can increase the plasma processing speed and uniformly perform plasma processing.

[Means for solving problems]

The plasma processing apparatus according to the present invention has a plurality of n (
n〉2) solenoid coils are arranged, and a magnetic field in which the magnetic field moves in the axial direction is formed by sequentially passing currents with different phases through the plurality of solenoid coils.

[Effect]

In the plasma processing apparatus according to the present invention, moving the magnetic field in the axial direction by sequentially passing currents with different phases through a plurality of solenoid coils is effective for plasma processing by reducing the diffusion of plasma toward the chamber wall surface. It is possible to increase the amount of plasma used and to perform uniform plasma processing on the substrate.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG. In FIG. 1, tlolfl plasma chamber +5+
A plurality of solenoid coils (I++) are arranged around the solenoid coils (10) so that their central axes do not coincide with each other.

Next, the operation will be explained. Plasma chamber (6)
A high frequency voltage is applied between the high frequency application electrode (11) and the counter electrode (4) from the high frequency power source (2) via the high frequency matching device (3) to generate plasma (7)f.

In addition, a power source (11) is connected to a plurality of solenoid coils (10).
), currents with different phases are passed sequentially to move the magnetic field in the axial direction. Here, as an example, a case where there are four solenoid coils will be explained.

As shown in Figure 2, four solenoid coils /I/
(log), (lob), (loc), (lod
) are spaced apart from the central axis of the plasma chamber (5) by a distance and are arranged at different angles of 90 degrees. 4 solenoid coils (
loa).

When currents with the current waveforms (a, b, c, d) shown in Figure 3 are applied to (lob), (10c), and (lod), respectively, the solenoid coils (log) and (lob)
, (IOC), (10d) rotates. Solenoid coil #
(1-Os), (10bL (1oc).

(10d), the magnetic field continues to rotate. Magnetic field strength solenoid coil (108), (10b),
(10(+).

(1 (M)) It is controlled by changing the current 1 flowing through it, and the turning radius can be changed depending on the distance.

4 solenoid coils (LOA), (10b),
(IOc).

The magnetic field exerted by (10d) is applied to the two electrodes (
1).

(4) Since it is almost perpendicular to the electrode surface, charged particles (ions and electrons) moving perpendicular to the electrode surface are not affected by the magnetic field.

On the other hand, among the charged particles generated between the two electrodes tl), [41, charged particles that move parallel to the electrode surface will diffuse from between the electrodes and reach the wall surface if there is no magnetic field, but if there is no magnetic field, the charged particles that move parallel to the electrode surface will diffuse from between the electrodes and reach the wall surface. When there is a magnetic field, the charged particles undergo a spiral movement around the magnetic lines of force due to the force of eV x B and are held between the electrodes for a long time, and the charged particles are effectively used in plasma processing, and when there is no magnetic field ( The plasma processing time is short for all cases.
magnetic flux density).

The above magnetic field is generated by four solenoid coils (10a).

In the case of a rotating magnetic field created by (10b), (1,Oc), and (lod), charged particles also rotate together with the rotating magnetic field, which effectively acts to uniformly perform plasma processing.

In this way, a plurality of solenoid coils (10a), (lob), (xoc
), (10d) are arranged around the chamber (5),
Forming a rotating magnetic field by sequentially passing current is to transfer the plasma generated between two electrodes (li, [4i) to electrode +1
) and +4i for a long time to reduce the plasma processing speed and to perform plasma processing in a negative manner.

In addition, in the above embodiment, four solenoid coils (log), (lob), (l
oo).

(10d) shows an example in which the current 1f shown in Fig. 3 is applied, but the number of solenoid coils may be plural, and the current waveform can also be an AC half wave in addition to the trapezoidal current waveform shown in Fig. 3. Even if a current waveform of a triangular wave, a triangular wave, or a pulse wave is sequentially passed through a plurality of solenoid coils, the same effect as in the above embodiment can be obtained.

〔Effect of the invention〕

As described above, according to the present invention, the plasma generated between the electrodes fl) and +4) provided in the chamber (5) is controlled by the kinetic magnetic field generated by the plurality of solenoid coils (10). The electrode (1) can be made to move linearly or rotatably and generate plasma for a long time.

(4) Since it is configured to be held in between, uniform and high-speed plasma processing can be performed over a wide area of the substrate (9).
The device can also be made at low cost and has the advantage of being highly accurate.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional side view showing a plasma processing apparatus according to an embodiment of the present invention, FIG. 2 is a plan view showing the arrangement of solenoid coils around the chamber in this embodiment, and FIG. FIG. 4 is a diagram showing the waveforms of four currents flowing respectively, and a schematic cross-sectional side view showing a conventional plasma processing apparatus. In the figure, (1) is a high frequency application electrode, (2) is a high frequency power source, (4) is a counter electrode, +5Hj plasma chamber, (7) is plasma, (9) is a workpiece (substrate), (1)
0g )~(lod)H solenoid coil, (II)i
It is a power source. In addition, the same reference numerals in the figures indicate parts corresponding to the same straddle.

Claims (1)

[Claims] (1) In a device that generates plasma between electrodes arranged apart in the direction of the central axis of the chamber and performs plasma treatment on a workpiece placed between the electrodes, A plasma processing apparatus characterized in that a plurality of solenoid coils are provided, each having a separate center axis substantially parallel to a central axis, and currents having different phases are sequentially passed through the plurality of solenoid coils.