JP2010034014A - Plasma processing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plasma processing device which improves uniformity of processing and a processing speed during ashing and cleaning. <P>SOLUTION: A two frequency power simultaneous supply batch type plasma processing device includes a decompressed reaction vessel 11. A first electrode 12 serving as a table for placing an object to be processed is installed, and high frequency power is supplied to it from an oscillator 13 having a frequency of 13.56 MHz through an impedance matching apparatus 14. Furthermore, low frequency power is simultaneously supplied to a second electrode 15 from an oscillator 17 of 40 KHz through a matching transformer 16. Reactive gas is introduced like a shower to a second electrode 15 from hollowly processed gas ejecting holes 22, and charged particles in plasma having high density and high energy which is generated by combination of high frequency power and low frequency power are horizontally and alternately accelerated and swung between the second electrodes 15 surrounding the object to be processed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

The present invention relates to a plasma processing apparatus used in manufacturing processes of semiconductors, liquid crystal devices, and electronic devices.

Japanese Patent Application No. 2002-332889 Japanese Patent Application No. 2002-373245

Conventionally, a batch type decompression reaction vessel having a pair of parallel plate type electrodes generates high-frequency power in one frequency band (mainly 13.56 MHz) to collectively process objects to be processed. Compared with performance, uniformity was inferior. Therefore, a plasma processing apparatus for simultaneously realizing a dramatic improvement in uniformity and processing time is provided.

Two pairs of parallel plate electrodes are provided in order to simultaneously supply power having different frequency bands in the vacuum reaction vessel. The table portion on which the workpiece is placed is also supplied with electric power from a first power source of 1 MHz or more that also serves as a discharge electrode via a matching circuit. Further, a second power source using a push-pull amplifier circuit is supplied via a matching transformer at a frequency range from 10 KHz to 100 KHz on both sides of the object to be processed at an optimum distance. The reaction gas is introduced from a jet hole that has been hollowed into a shower shape from the second electrode, and the charged particles in the high-density and high-energy plasma generated are alternately accelerated from side to side and swung between the electrodes. It is possible to uniformly perform plasma processing on the entire surface of the substrate, in particular, the center portion such as a long one that is normally stored in a jig or the like having a narrow gap, which is difficult for plasma to enter.

Compared to the conventional batch type plasma processing equipment, the processing uniformity and processing time have been dramatically improved and improved.

Hereinafter, the best embodiment of the present invention will be described with reference to the drawings.

The batch type plasma processing apparatus for simultaneous dual-frequency power supply of the present invention includes a reduced pressure reaction vessel 11 and generally uses aluminum or stainless steel as its material. The vacuum reaction vessel 11 is grounded to the housing, and the first electrode 12 also serving as a table portion on which the object to be processed is placed is installed, and a high frequency power is supplied from an oscillator 13 having a frequency of 13.56 MHz and a maximum output of 1 KW through an impedance matching unit 14. Is supplied. Furthermore, low frequency power is simultaneously supplied to the second electrode 15 from the oscillator 17 having a maximum output of 2 KW via the matching transformer 16. The reaction gas is introduced into the second electrode 15 from a gas outlet 22 that has been hollowed into a shower shape, and charged particles in the high-density and high-energy plasma generated by the combination of high-frequency power and low-frequency power are processed. Acceleration and rocking alternately between the left and right electrodes 15 between the two surrounding electrodes have dramatically improved and improved the processing which has been uneven and incomplete. The reaction gas used is generally oxygen, argon, nitrogen, helium or the like. Further, the exhaust ports 18 are provided on both the left and right sides of the reduced pressure reaction vessel 11 and are connected to the vacuum pump 19. The object to be processed is mainly the magazine insertion printed board 20, the quartz boat insertion wafer 21 and the like, but any use can be used as long as the present invention can be applied.
Next, a series of processing processes of this plasma processing apparatus will be described. First, when the start signal is turned on, evacuation starts, and when the inside of the reduced pressure reaction vessel reaches a predetermined degree of vacuum, the reaction gas is introduced and a certain period of time (usually 10 to 60 seconds) is set to 13.56 MHz high frequency power. And low frequency power of 40 KHz are simultaneously supplied to start plasma discharge. After that, when a predetermined vacuum degree is reached again after the processing time set in advance in the recipe is reached, the process proceeds to purging and when the pressure returns to the atmospheric pressure, the end buzzer sounds and the loop process ends.

It is a schematic sectional drawing which shows the inside of the pressure reduction reaction container of the plasma processing apparatus of this invention. It is a top view which shows the 2nd electrode by this invention roughly.

Explanation of symbols

11 vacuum reaction vessel, 12 first electrode (table part), 13 impedance matcher, 4 oscillator 13.56 MHz, 15 second electrode, 16 matching transformer, 17 oscillator 40 KHz, 18 exhaust port, 19 vacuum pump, 20 workpiece (Magazine insertion printed circuit board), 21 workpiece (quartz boat insertion silicon wafer), 22 hollow hole processing gas jet.

Claims (6)

A plasma processing apparatus characterized by efficiently supplying electric power having frequencies in different bands into a decompression reaction vessel to efficiently perform etching, ashing, cleaning, and the like of an object to be processed. The plasma processing apparatus according to claim 1, wherein the frequency of the power applied to the pair of electrodes is in a range of 10 KHz to 100 KHz, and the frequency applied to the other electrode is a band of 1 MHz to 100 MHz. 2. The plasma processing apparatus according to claim 1, wherein electric power using a push-pull amplifier circuit is supplied to the electrodes in the frequency band of 10 kHz to 100 kHz through a matching transformer. 2. The plasma processing apparatus according to claim 1, wherein a plurality of reaction gas supply ports are provided in a shower shape on a pair of electrodes for supplying power in a frequency band of 10 KHz to 100 KHz. The reaction gas outlets of the pair of electrodes for supplying power in the frequency band of 10 KHz to 100 KHz are subjected to hollow hole processing. The size of the hollow hole processing is 1 mm or more in diameter and 1 mm or more in depth, and each interval between the hollow holes is also 1 mm or more.

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