Profiling Photoinduced Carrier Generation in Semiconductor Microwire Arrays via Photoelectrochemical Metal Deposition.
Au was photoelectrochemically deposited onto cylindrical or tapered p-Si microwires on Si substrates to profile the photoinduced charge-carrier generation in individual wires in a photoactive semiconductor wire array. Similar experiments were repeated for otherwise identical Si microwires doped to be n-type. The metal plating profile was conformal for n-type wires, but for p-type wires was a function of distance from the substrate and was dependent on the illumination wavelength. Spatially resolved charge-carrier generation profiles were computed using full-wave electromagnetic simulations, and the localization of the deposition at the p-type wire surfaces observed experimentally correlated well with the regions of enhanced calculated carrier generation in the volumes of the microwires. This technique could potentially be extended to determine the spatially resolved carrier generation profiles in a variety of mesostructured, photoactive semiconductors.
Division of Chemistry and Chemical Engineering, ‡Division of Engineering and Applied Sciences, ∥Kavli Nanoscience Institute, and ⊥Beckman Institute, California Institute of Technology , Pasadena, California 91125, United States.
Mita
M
Dasog
Division of Chemistry and Chemical Engineering, ‡Division of Engineering and Applied Sciences, ∥Kavli Nanoscience Institute, and ⊥Beckman Institute, California Institute of Technology , Pasadena, California 91125, United States.
Azhar I
AI
Carim
Sisir
S
Yalamanchili
Harry A
HA
Atwater
Division of Chemistry and Chemical Engineering, ‡Division of Engineering and Applied Sciences, ∥Kavli Nanoscience Institute, and ⊥Beckman Institute, California Institute of Technology , Pasadena, California 91125, United States.
Nathan S
NS
Lewis
Semiconductor; carrier generation; electrodeposition; microwires; photoelectrochemistry; silicon