The Preparation Of Silver Thin Film On Silicon Substrate By Two-step Method

In such as large scale integrated circuit manufacturing and very large scale integrated circuit manufacturing semiconductor industry, silicon is a very important raw materials. Also, it can be widely used in microelectromechanical system and solar battery manufacturing. And silver as the positive electrode materials of the solar cells and the connection metal in the integrated circuit industry, all has the widespread application, so the preparation of silver thin film on silicon surface has important significance. Electrochemical deposition is a safe, controllable, low cost and easy way to operate and also is a preparation process which is saving energy and environment friendly, so in this thesis using the chemical and electrochemical two-step method to looking for a simple and easy way to make the silver thin film on P type silicon surface.Using the two-step method to fabricate micron-grade silver thin film on P type silicon surface, in the first step silicon substrate was placed in HF solution with AgNO3, in HF environment Ag+ions were reduced to Ag and then deposit on the surface of silicon to form the discontinuous Ag nanoparticles seed layer. In the second step the silicon with Ag seed layer was used as the anode in AgNO3and KNO3solution to electrodeposit silver thin film by electrochemistry constant current method to get the silver thin film which we need. Respectively finding the suitable conditions for the preparation of silver nanoparticles seed layer and micron-grade silver thin film on silicon surface.In order to analyze the structure of silver thin film, the size of crystal particle, surface morphology and the thickness of the film, X-ray diffraction spectrum (XRD) and scanning electron microscopy (SEM) were used separately for study, finding that in the first step the deposition of silver seed layer in0.02g/L AgNO3and5%HF solution was well and in second step the silver thin film performed well at the current of-1.5mA in0.1mol/L AgNO3and0.1mol/L KNO3solution for3hours.