Atomic Layer Deposition of Titanium Oxide-Based Films for Semiconductor Applications—Effects of Precursor and Operating Conditions
oleh: Vladyslav Matkivskyi, Oskari Leiviskä, Sigurd Wenner, Hanchen Liu, Ville Vähänissi, Hele Savin, Marisa Di Sabatino, Gabriella Tranell
| Format: | Article |
|---|---|
| Diterbitkan: | MDPI AG 2023-08-01 |
Deskripsi
Two widely used atomic layer deposition precursors, Tetrakis (dimethylamido) titanium (TDMA-Ti) and titanium tetrachloride (TiCl<sub>4</sub>), were investigated for use in the deposition of TiOx-based thin films as a passivating contact material for solar cells. This study revealed that both precursors are suited to similar deposition temperatures (150 °C). Post-deposition annealing plays a major role in optimising the titanium oxide (TiO<sub>x</sub>) film passivation properties, improving minority carrier lifetime (τ<sub>eff</sub>) by more than 200 µs. Aluminium oxide deposited together with titanium oxide (AlO<sub>y</sub>/TiO<sub>x</sub>) reduced the sheet resistance by 40% compared with pure TiO<sub>x</sub>. It was also revealed that the passivation quality of the (AlO<sub>y</sub>/TiO<sub>x</sub>) stack depends on the precursor and ratio of AlO<sub>y</sub> to TiO<sub>x</sub> deposition cycles.