Method for detecting minority carrier lifetime of semiconductor nanowire

Abstract

The invention discloses a method for detecting the minority carrier lifetime of a semiconductor nanowire. The method comprises the following steps of: measuring the light excitation current response of a single nanowire under Schottky reverse bias by using a conductive scanning probe, performing quantitative fitting on a light current-bias curve by using a numerical model, and determining the minority carrier lifetime of the semiconductor nanowire. The method is suitable for measuring the carrier dynamic characteristic of the single nanowire in a nanowire sample prepared by an epitaxial method, an etching method and the like; and light excitation intensity is low, and the working state of the nanowire in a photoelectric device is approached, so the method has great significance for analyzing and evaluating the core performance of the nanowire and the photoelectric device.

Description

technical field [0001] The invention relates to the detection of low-dimensional structure semiconductor materials, in particular to a novel measurement method for the lifetime of minority carriers of semiconductor nanowires. Background technique [0002] Semiconductor nanowires have gained considerable attention in the fields of photodetection and solar energy harvesting due to their unique structures and optoelectronic properties. The minority carrier lifetime (hereinafter referred to as the minority carrier lifetime) is the main factor determining the photoelectric performance of the device. Due to the high surface-to-volume ratio of nanowires, surface scattering has a significant impact on their minority carrier lifetimes, which is very different from bulk materials. Therefore, the extraction of the lifetime of a single nanowire has very positive significance for the optimization of its material properties and the performance improvement and application of devices. [...

AI Technical Summary

Problems solved by technology

The relative deficiencies and limitations of this type of method are: 1) It is necessary to prepare a single nanowire device, the process requirements and costs are high, and the process such as photolithography, corrosion, etc. will cause the decline of the photoelectric performance of the nanowire, resulting in the extraction of parameters possible departure from the original properties of the nanowire

3) The resolution of this method to measure the minority carrier diffusion length of nanowires depends on the spot diameter, and it is powerless when the minority carrier diffusion length to be measured is close to or even smaller than the excitation spot size (shorter minority carrier lifetime)

For direct bandgap semiconductor nanostructures, the minority carrier lifetime is often at the level of nanoseconds or even picoseconds, and the diffusion length is as short as hundreds to tens of nanometers.

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