Semiconductor materials are the basic materials of microelectronic devices and photovoltaic devices. Their impurity and defect characteristics seriously affect device performance. With the increase in the integration of microelectronic devices and the conversion efficiency of photovoltaic devices, the requirements for semiconductor raw materials are increasing. In order to meet the needs of industrial production, the material detection method is required to have higher sensitivity and faster measurement speed, while avoiding damage to the material. Carriers are functional carriers of semiconductor materials, and their transport characteristics determine the performance of various optoelectronic devices, including carrier lifetime, diffusion coefficient, and surface recombination rate. Optical carrier radiation technology is a kind of all-optical non-destructive testing method for simultaneous measurement of carrier transport parameters, but this method still has some limitations in the measurement and characterization of carrier transport parameters, such as the theoretical model Applicability, measurement accuracy and speed of parameters.
With the support of the National Natural Science Foundation of China, the Institute of Optoelectronic Technology of the Chinese Academy of Sciences aimed at the above problems and established a nonlinear photocarrier radiation model with traditional semiconductor silicon materials as the research object, and on this basis, respectively proposed multi-spot light The carrier radiation technology and steady-state photocarrier radiation imaging technology have confirmed the effectiveness of the above technology through simulation calculations and experimental measurements. Multi-spot light carrier radiation technology can completely eliminate the influence of the frequency response of the measurement system on the measurement results, and improve the measurement accuracy of the carrier transport parameters. The P-type single crystal silicon with a resistivity of 0.1-0.2Ω? Cm is For example, the proposed multi-spot light carrier radiation technology reduces the measurement uncertainty of carrier lifetime, diffusion coefficient and surface recombination rate from traditional ± 15.9%, ± 29.1% and> ± 50% to ± 10.7%, ± 8.6% and ± 35.4%. In addition, the steady-state photocarrier radiation imaging technology simplifies the theoretical model and measurement device, the measurement rate is greatly improved, and has greater industrial application potential.