Abstract: [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.

Abstract: Provided is a method and a device for measuring a temperature which can recognize the temperature of a semiconductor layer directly with high precision when the semiconductor layer is formed by deposition. The quantity of laser light transmitted a semiconductor layer is monitored by a photodetector by using laser light having a wavelength As at which the transmittance of light changes abruptly when the temperature of the semiconductor layer reaches Ts during or after deposition. When heat being given to the semiconductor layer is changed, the quantity of laser light monitored by the photodetector changes abruptly when the temperature of the semiconductor layer reaches Ts at a time A, B or C. Consequently, the fact that the temperature of the semiconductor layer reached Ts at a time A, B or C can be recognized exactly, and an error in temperature information observed by a device for measuring temperature variations can be calibrated, for example.