Multi-component mono-crystal prodn. using congruent melt - under protective melt and inert gas pressure preventing vaporisation

摘要

A multi-component monocrystal is grown from a melt (I), surrounded by a protective melt (pref. B2O3) in an open crucible and under an external inert gas (pref. Ar) pressure rather higher than the vapour pressure of the volatile component (II) of (I) at the m. pt. to prevent vaporisation of (II), the mixt. being adjusted to and kept at a congruent melt state during growth with S or Se. The monocrystal pref. consists of Fe1-xAxSy or B'Sey (in which 0= x =1; 1.0 =y =1.1; A is Ti, V, Cr, Co or Ni; B' is Fe, Cr, CO or Ni). The monocrystals are used esp. as pyroelectric detectors. The process prevents local variation in the crystal compsn. such as inclusions of foreign phases, pores, cracks, etc.