Title:
METHOD AND APPARATUS FOR DISCRIMINATING ETCHING END POINT AND METHOD OF ETCHING INSULATING FILM
Document Type and Number:
Japanese Patent JP3383236
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To provide a method and apparatus for discriminating an etching end, which can perform an etching end discrimination for a semiconductor wafer stably, even if the semiconductor wafer has a low effective aperture rate.
SOLUTION: A method of determining etching end for dry etching comprises the steps of reducing noises contained in an input signal waveform using a first digital filter 18; calculating differential coefficients (first-order or second- order) of the signal waveform by a differentiating process performed by a differential coefficient calculation circuit 19; calculating a smoothed differential coefficient value by reducing, using a second digital filter 20, noise components of time-series differential coefficients calculated in the previous step; and discriminating an etching end by causing a discrimination means 22 to compare this smoothed differential coefficient value with a preset value.
Inventors:
Takehito Usui
Ken Yoshioka
Shoji Ikuhara
Koji Nishihata
Master Takahashi
Tetsunori Kaji
Shigeru Nakamoto
Ken Yoshioka
Shoji Ikuhara
Koji Nishihata
Master Takahashi
Tetsunori Kaji
Shigeru Nakamoto
Application Number:
JP10727199A
Publication Date:
March 04, 2003
Filing Date:
April 14, 1999
Export Citation:
Assignee:
株式会社日立製作所
株式会社 日立インダストリイズ
株式会社 日立インダストリイズ
International Classes:
H01L21/302; C23F4/00; H01L21/3065; H01L21/60; H01L21/66; H01L21/768; (IPC1-7): H01L21/3065; C23F4/00
Domestic Patent References:
| JP8232087A | ||||
| JP61112927A | ||||
| JP653179A | ||||
| JP936095A | ||||
| JP6071922A | ||||
| JP10313009A | ||||
| JP9266098A |
Attorney, Agent or Firm:
Katsuo Ogawa