Contribution of ions to the growth of am

The growth of amorphous, microcrystalline, and polymorphous silicon thin films has been studied to understand the contributions of various species to film formation. This investigation focused on the surface reaction probabilities of radicals involved in silicon deposition processes. Hot wire chemical vapor deposition (HW-CVD) was employed to analyze the growth mechanisms, revealing that the surface reaction probability for the depositing radical in amorphous silicon is consistent with SiH3, while values for microcrystalline silicon growth are notably higher. In contrast, plasma-enhanced chemical vapor deposition (PECVD) demonstrated a reliance on more reactive radicals than SiH3 in forming amorphous silicon, indicating a transition towards ion-dominated growth mechanisms for polymorphous and microcrystalline silicon, where ions can account for up to 70% of the deposited material. This ion dominance is attributed to effective silane ionization through charge exchange with hydrogen ions. Furthermore, the etching of amorphous silicon using hydrogen plasma pointed towards possible hindrances in the deposition process due to ion interactions. The findings highlight the complexity of deposition dynamics and suggest pathways for improving the quality of silicon thin films in practical applications.