US Patent 11190132 Photocurrent scanning system

A photocurrent scanning system comprises a laser generating device, a focusing device, a displacement adjustment device, a bias supply device, and a measuring device. The laser generating device is used to emit a laser. The focusing device is used to focus the laser to a surface of a sample. The displacement adjustment device is used to place the sample and adjust a position of the sample, to make the laser focused onto different parts of the surface of the sample. The bias supply device is used to supply a voltage to the sample. The measuring device is used to measure a photocurrent signal flowing through the sample.