| 摘要 |
An optical film thickness meter capable of measurement of an optical film thickness and spectroscopic characteristics with high accuracy and a thin film forming apparatus provided with the optical film thickness meter are provided. The optical film thickness meter includes a light projector (11), a reflection mirror (17), a light receiver (19), and a monochromator (20), and the reflection mirror (17) has a reflection surface disposed substantially perpendicularly to the optical axis of measurement light on the side opposite to an actual substrate (S) with respect to an incident direction of the measurement light. Also, the actual substrate (S) is disposed having a predetermined inclination angle (±) with respect to the optical axis of the measurement light. The measurement light (outgoing light and reflection light) passes through the actual substrate (S) twice, whereby a change amount in transmissivity (light amount) can be increased, and control accuracy of film thickness measurement can be improved. Also, occurrence of a measurement error caused by a difference in transmission positions can be prevented, and since the measurement light which has not passed through the measurement substrate twice along a predetermined path is no longer detected on the light receiver (19) side, the optical film thickness and spectroscopic characteristics can be measured with high accuracy. |
