Passivation of crystalline silicon

There are applications that involve crystalline semiconductors in which the properties of a-Si H can be used to great advantage in improving the performance of already well-known crystalline devices. In addition, new structures are possible that would not be readily achieved with crystalline silicon (c-Si). 

The properties specific to a-Si H that we propose to exploit in hybrid structures are the abundance of hydrogen, the wide energy band gap, and the high dielectric constant or refractive index. 

Exposure of virgin diodes to molecular hydrogen (H2) lowers the leakage current by a factor of five. Subsequent exposure to atomic hydrogen gives a further decrease in leakage current by two ordeis of magnitude. 

The data of Fig. 3 show the reverse-bias I- V characteristics for two representative p-n junctions. The one labeled Iox was passivated with thermal oxide, the one labeled /a.Si H was passivated with a-Si H. It is striking that the leakage current of the a-Si H-passivated junction is two orders of magnitude lower than that of the Si02 -passivated diode. 

Note that the I- V characteristics appear exponential over most of the bias 

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