The Surface Photovoltaic and Photoluminescent Evolution of a Silicon Nanoporous Pillar Array for Different Etching Times

Abstract

A series of silicon nanoporous pillar array (Si-NPA) samples are prepared with different times of hydrothermal etching, and their surface morphologies are characterized. A systematic study on the evolution trend of the surface photovoltage and photoluminescence spectra discloses that the adoption of a prolonged etching time will increase the native degree of oxidation and decrease the interfacial states density localized in the SiO𝑥 matrix. These results might be helpful for designing Si-NPA-based semiconductor nanosystems with optimized physical properties.

The Surface Photovoltage Mechanism of a Silicon Nanoporous Pillar Array

“…[19−25] In the SPV method, the illumination-induced changes in the surface potential of the semiconductor are measured by a nondestructive and noncontact method. [19,20] In our previous work, [26] it was found that the SPV spectrum of Si-NPA is obviously different to that of single crystal silicon (sc-Si) and the SPV mechanism of Si-NPA needs to be further clarified. In this Letter, the SPV properties of the Si-NPA sample are studied first by using SPV spectroscopy.…”