| 摘要 |
PURPOSE:To measure the carrier concentration and mobility quickly without damaging the sample, by irradiating beam of a certain wavelength and calculating the intensity signal of the transmitted beam. CONSTITUTION:By rotating holder 3 which turns light beam into single colored beam with wavelength which corresponds to transition inside band and free carrier absorption through filters 4 and 5, the filters can be changed over and beam of a certain wavelength can be obtained. The single colored light beam is irradiated on a measured sample 6, and detecting 7 the strength of transmitted beam, absorption coefficient is calculated 8. As there is proportional relationship among light absorption coefficient of the transition inside band, carrier concentration, and light absorption coefficient (carrier concentration)/(mobility), carrier concentration and mobility can be calculated by programming above relation in the arithmetic unit 8. |
