MOLECULAR BEAM EPITAXIAL DEVICE

PURPOSE:To produce a crystal with excellent quantity by measuring and controlling accurate temperature of a substrate by a method wherein a radiothermometer and a black body radiative source are arranged on positions symmetric with a perpendicular drawn on the surface of a substrate to control the temperature of black body radiative source and the substrate independently. CONSTITUTION:When a substrate 2 is mirror-reflected, the calories Q per unit area measured by a radiothermometer 8 are represented by the reflection between the temperature TW of substrate 2 and the temperature TB of a black body radiative source 10. The temperature TB of black body 10 is measured by a thermocouple 11. Therefore, when the temperature TB of another black body radiative source 11 is independently fluctuated in two ways by a heater 13 and the respective calories Q are measured by the radiothermometer 8, the temperature TWof substrate 2 and the emissivity epsilon can be calculated. Through these procedures, the absolute temperature of substrate 2 can be measured making it feasible to control the output froml another heater 5 by means of feeding back the absolute temperature thus measured.