| 摘要 |
<p>[Problem] An apparatus and method for measuring luminescence decay due to the lifetime of energy carriers inside a material such as a semiconductor is presented. [Solution] The intensity of a laser is modulated by a light modulating device resulting in a square wave excitation 14, and applied to a semiconducting material. The energy carriers inside the semiconductor are excited, and recombine after a certain time to give rise in part to some light emission 24, which decays in intensity from the time at which the excitation periods end. The decaying light is separated from the light emitted during excitation by another light modulator resulting in 26. This light intensity 26 contains the information related to the carrier lifetime. Because the amount of this light 26 is small and has a very short emission time, a CCD detector is used to be integrated several cycles of the decay periods in order to obtain a reasonable signal. This integrated intensity signal can be used to determine the carrier lifetime.</p> |
