Study on an improved MWECR CVD system and preparation of silicon-substrate thin films

In this paper, aiming at the problems existed in the conventional MWECR CVD system using to prepare silicon-substrate thin films, such as lower microwave transform power, lower plasma density and higher photodegradation etc., the system was improved necessarily and efficiently, in which we focused on the studies for the microwave coupling structure, magnetic field structure and deposition system structure. The experimental results showed that the improved microwave coupling structure can produce high-microwave-transform efficiency of about 90%, the improved magnetic field structure can not only reduce the weight and volume of the conventional system but also obtain higher magnetic field strength which was two times that of the single coil magnetic field and useful to obtain higher plasma density on the sample holder, and the addition of the hot wire system can make the photodegradation decrease remarkably. In the result, the thin films prepared by using this improved system performed excellent properties, such as high photosensitivity of 1.54×105, high deposition rate of about 1 nm/s and low photodegradation, etc.