Fabrication method of semiconductor integrated circuit device

摘要

An object of the present invention is to provide a fabrication method of a semiconductor integrated circuit device capable of improving the throughput, reducing the cost of a cleaning gas and prolonging the life of a process kit by automatically detecting the end point of cleaning in a chamber. A cleaning gas converted into plasma in a plasma gas generator is introduced into a chamber to remove an unnecessary film deposited over the interior wall of the chamber or electrode. By an RF power source adjusted to low output from the film formation time, a high frequency voltage is applied to a lower electrode and an upper electrode. This voltage is detected by an RF sensor and amplified by an electronic module. The voltage thus amplified by the electronic module is input to a termination controller. The termination controller automatically judges the termination of cleaning when the voltage thus input becomes substantially constant at a predetermined voltage or greater.