Symmetric Dopant-Free Si Solar Cells Enabled by TiO_x Nanolayers: An In-Depth Study on Bipolar Carrier Selectivity.

ABSTRACT: High-efficiency solar cells require two contact structures, engineered for efficient extraction of photogenerated holes and electrons at the respective electrodes. Herein, crystalline Si solar cell featuring hole- and electron-selective passivating contacts composed entirely of a single material, amorphous titanium oxide (TiO_x), without extrinsic doping is demonstrated. The hole/electron selectivity of the TiO_x layers (≈5 nm) is tailored by the oxidation process and the choice of Ti precursor in the atomic layer deposition (ALD). Ex situ and in situ X-ray photoelectron spectroscopy measurements elucidate that the hole-selective TiO_x induces significant band bending in the Si (Φ≈0.7 eV), generating a p-type inversion layer in the n-Si absorber. The electron-

SUBMITTER: Matsui T 

PROVIDER: S-EPMC11744698 | biostudies-literature | 2025 Jan

REPOSITORIES: biostudies-literature