Method for monitoring plasma processing apparatus

Abstract

The present apparatus comprises a vacuum process chamber 100 that contains an upper electrode 110 having a conductive plate 115 with gas supply holes for supplying a process gas and a lower electrode 130 having a platform on which a sample is to be mounted; process gas supply means 117 for supplying the process gas to the gas supply holes in the upper electrode 110 and exhaust means 106 for exhausting the vacuum process chamber; a high frequency power supply 121 for applying a high frequency power to the upper electrode to generate a plasma between the upper and lower electrodes; a high frequency bias power supply 122 for applying a high frequency power to the upper electrode to generate a direct current bias potential in the upper electrode; and abnormal discharge determination means 152 for determining whether an abnormal discharge has occurred or not based on the direct current bias potential generated in the upper electrode.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to the apparatus and method for monitoring a plasma processing apparatus. In particular, it relates to the apparatus and method for monitoring a plasma processing apparatus that reduces the processing failure caused by an abnormal discharge. [0003] 2. Description of the Related Art [0004] In semiconductor manufacturing processes, plasma processing apparatus are widely used for micromachining processes, such as etching, film deposition and ashing. In a process involving plasma processing, a process gas introduced into a vacuum chamber (reactor) is changed into a plasma by plasma generator means and the plasma is caused to react with a surface of a semiconductor wafer to implement micromachining, and a volatile reaction product is discharged, thereby accomplishing the predetermined process. [0005] With such a plasma processing apparatus, if the apparatus is used for a long time, component...

AI Technical Summary

Benefits of technology

[0013] The present invention comprises a vacuum process chamber that contains an upper electrode having a conductive plate with gas supply holes for supplying a process gas and a lower electrode having a platform on which a sample is to be mounted; process gas supply means for supplying the process gas to the gas supply holes in the upper electrode and exhaust means for exhausting the vacuum process chamber; a high frequency power supply for apply

Problems solved by technology

Such a larger gap or holes may result in another plasma occurring in the defined space.

If the abnormal discharge occurs, a dissociation state of the process gas changes to deteriorate the etching capability thereof, or a reaction product film formed in the reactor is peeled off creating a foreign matter.

Therefore, if components are worn and deteriorated causing abnormal discharge to occur, a normal etching can no longer be accomplished.

However, abnormal discharge sometimes occurs before the elapse of reference time for component replacement.

Thus, by that time, a considerable amount of poorly processed wafers would have resulted.

Besides, according to the method described in the Japanese Patent Laid-Open No. 9-92491 described above, while the abnormal discharge occurring in the plasma can be detected, any abnormal discharge occurring with the inner portion of the gas hole of the upper electrode as described above cannot be detected.

Images