Abstract
The effect of high-temperature anneals on low-pressure chemical-vapor deposited (LPCVD) Si3 N4 /thermally grown SiO2 stacks on silicon wafers has been studied. Annealing in a nitrogen atmosphere at 900 or 1000°C for 30 min causes a substantial reduction in both N-H and Si-H bond concentration in the nitride film and a significant degradation of surface passivation. Subsequent anneals in forming gas (95% Ar/5% H2) at temperatures in the range 800-900°C lead to a gradual reformation of N-H and Si-H bonds and an improvement in surface passivation. It is hypothesized that the chief mechanism responsible for the improvement in surface passivation is the passivation of defects at the Si- SiO2 interface with atomic hydrogen, supplied by the breaking of N-H and Si-H bonds in the nitride film. Samples with SiO2 Si3 N4 stacks display excellent surface passivation following high-temperature forming gas anneals, indicating that such treatments can be used for photovoltaic applications, where surface passivation as well as good optical properties are important.
Original language | English |
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Article number | 033608JES |
Pages (from-to) | G750-G754 |
Journal | Journal of the Electrochemical Society |
Volume | 153 |
Issue number | 8 |
DOIs | |
Publication status | Published - Aug 2006 |