Title:
【発明の名称】物質の蒸着速度の制御方法
Document Type and Number:
Japanese Patent JP2974253
Kind Code:
B2
Abstract:
The thickness and rate of growth of a deposited film is monitored using a piezoelectric crystal sensor such as an AT-cut plano-convex crystal. The frequencies of the fundamental frequency and another resonance mode are measured prior to deposition, and the change of these two frequencies is monitored during deposition. The areal mass density of the deposited material is determined from these two resonance frequencies for the uncoated quartz crystal and for the crystal during deposition. A frequency generator provides accurate sweeps of frequency which are applied to the crystal, and the crystal response is supplied to a phase detector to identify the positions of the resonance frequencies. The acoustic impedance ratio Z of the deposited material relative to the fresh crystal is computed from the resonance frequencies for the coated and uncoated crystal, by applying the modal equations for AT-cut plano-convex quartz crystal and Lu-Lewis relation. From the frequency shifts and acoustic impedance ratio, and areal mass density can be calculated. The same crystal can be used to control the growth rate of several successive layers.
Inventors:
ABUDOORU WAJIDO
Application Number:
JP31525690A
Publication Date:
November 10, 1999
Filing Date:
November 20, 1990
Export Citation:
Assignee:
REIBORUDO INFUIKON INC
International Classes:
C23C14/54; G01B7/06; G01B17/02; G01B17/06; (IPC1-7): G01B17/02; C23C14/54
Domestic Patent References:
| JP5739171A | ||||
| JP57106808A | ||||
| JP6093303A | ||||
| JP5937510U |
Attorney, Agent or Firm:
Yoshihisa Oshida