Summary: | 碩士 === 國立交通大學 === 應用化學研究所 === 86 ===
Silicon to silicon anodic bonding by use of sputter deposited borosilicate film is a promising mounting method for microelectromechanical systems (MEMS).The advantages of the silicon to silicon anodic bonding were like its reliability and flexibility in contrast to the wide use of anodic bonding with Pyrex glass substrates. Boron glass has a strong tendency to form born acid. on the surface that makes bonding impossible or with a high process temperature for safe bonding. Also, the low deposition rates sputtering of glass layers is time consuming and difficult to control the composition of the sputtered glass layers ect.
In this thesis, we present the preparation of glass layers that were suitable for the anodic bonding of two silicon substrates using spin on glass. In this process a liquid sol solution is used within a spin coating process. The solution is a mixture based on organic silicon containing compounds, like TEOS (Tetremethy1 orthodilicate), and a sodium salt all dissolved in ethanol. After a careful thermal treatment, silica film containing about 5% wt. Na2O can be obtained with a thickness in the range from 100nm to 300nm is one deposition step. Anodic bonding of two silicon substrates is possible with films at bonding temperature 350℃ and the optimized bonding strength is 5.86 MPa for applied voltage 160V at 400℃.
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