In recent years, a flexible type of solar cell that can maintain various shape changes and that is applicable to virtually all products has attracted global attention. In the present research, we describe equipment for the production of thin-film material for flexible type solar cells that uses a high-frequency plasma chemical vapor deposition (CVD) method. This equipment is now at the development stage, and in order to clarify the cardinal trait of the plasma, we performed a plasma treatment on the surface of a Si wafer. Using X-ray photoelectron spectroscopy and contact angle meter measurements, we identified one index that clarifies the simple cardinal trait of plasma CVD.