Effect of hydrogen plasma precleaning on the removal of interfacial amorphous layer in the chemical vapor deposition of microcrystalline silicon films on silicon oxide surface

Microcrystalline silicon(μc-Si) film deposited on silicon oxide in a remote plasma enhanced chemical vapor deposition (RPECVD) with disilane (Si2H6) and silicon tetrafluoride (SiF4) has been investigated. It was found that in situ hydrogen plasma cleaning of the substrate prior to deposition is effective to reduce the interfacial amorphous transition region. It is believed that hydrogen plasma cleaning generated adsorption and nucleation sites by breaking weak Si–O and Si–Si bonds and also removed oxygen/carbon impurity. Surface roughening was observed from the hydrogen plasma precleaning which helped nucleation and crystallization at the initial stage of the growth.