Short time electron cyclotron resonance hydrogenation of polycrystalline silicon thin-film transistor structures

Electron cyclotron resonance plasmas have been used to produce the most effective, shortest time plasma hydrogenation of thin-film polycrystalline silicon transistors yet reported. We demonstrate that significant improvement in device characteristics can be achieved with these plasmas using exposure times of the order of only 1 min and that 5 min exposures give saturated characteristics of a 2 V threshold voltage, a 65 cm2/V s mobility, and a 107 on/off ratio. We also explore the pressure and power level dependence of this passivation, as well as the effects of shielding with a grid, and show that the more efficient and more stable electron cyclotron resonance hydrogen exposures are at lower pressures.