Electrical and chemical characterization of Al2O3 passivation layer deposited by plasma-assisted atomic layer deposition in c-Si solar cells

Aluminum oxide (Al
₂
O
₃
) film by atomic layer deposition (ALD) is known to supply excellent surface passivation properties on crystalline Si surface. In this study, 10 nm Al
₂
O
₃
film was deposited on crystalline silicon by plasma-assisted atomic layer deposition (PAALD). To optimize concentration of hydrogen in Al
₂
O
₃
film, deposited RF power was changed from 100 W to 900 W. Then, annealing and firing process were conducted. After annealing and firing, fixed charge in Al
₂
O
₃
film was calculated by conductance-voltage measurement (C-V) and structure change was analyzed by XPS because the structure is related to fixed charge.