The fabrication and characterization of flexible single-crystalline silicon and germanium p-intrinsic-n photodetectors on plastic substrates

Abstract

The flexible photodetector is the essential device for many of the optoelectronic applications and its performance can be influenced by a number of factors, including semiconductor materials, illumination conditions, device structures, etc. Therefore, in order to better design and use the flexible photodetectors, it is necessary to understand how these factors affect their performance. In this study, we fabricated flexible lateral p-intrinsic-n photodetectors formed with single-crystalline silicon and germanium nanomembranes on polyethylene terephthalate substrates. The performance of the flexible photodetectors with various dimensions is presented under different illumination conditions. The influences of different semiconductor materials, illumination conditions (wavelength and power of the incident light), and dimensions of the intrinsic region (length and width) on the photocurrent and efficiency are investigated, and the underlying mechanisms are studied based on experimental, simulation, and theoretical analysis. The results provide guidelines for the design and fabrication of flexible single-crystalline semiconductor photodetectors on the plastic substrates.