Verfahren und Vorrichtung vom Typ Czochralski zur Herstellung von Halbleitereinkristallen

摘要

An apparatus (10) for producing a semiconductor single-crystal (S) grown by the Czochralski method includes a reference reflector (12) disposed at the lower end of a gas rectifying tube (P), first and second optical systems (16, 20) disposed above the reference reflector for changing the direction of propagation of light from the horizontal to the vertical, and vice versa, a first position sensor (14) composed of a first light source for emitting a light beam in a horizontal direction toward the first optical system, and a first photosensitive member which receives a reflection light reflected from the melt surface (24) in a crucible (C), a second position sensor (18) composed of a second light source for emitting a light beam in a horizontal direction toward the second optical system, and a second photosensitive member which receives a reflection light reflected from the reference reflector. With this construction, the distance between the gas rectifying tube and the melt surface can be detected and maintained constant throughout the crystal growth process with the result that the crystal quality, especially the concentration of dopant and impurities such as oxygen and carbon crystal is uniform.