Abstract: A method and apparatus for growing truly bulk In2O3 single crystals from the melt, as well as melt-grown bulk In2O3 single crystals are disclosed. The growth method comprises a controlled decomposition of initially non-conducting In2O3 starting material (23) during heating-up of a noble metal crucible (4) containing the In2O3 starting material (23) and thus increasing electrical conductivity of the In2O3 starting material with rising temperature, which is sufficient to couple with an electromagnetic field of an induction coil (6) through the crucible wall (24) around melting point of In2O3. Such coupling leads to an electromagnetic levitation of at least a portion (23.1) of the liquid In2O3 starting material with a neck (26) formation acting as crystallization seed. During cooling down of the noble metal crucible (4) with the liquid In2O3 starting material at least one bulk In2O3 single crystal (28.1, 28.2) is formed.

Abstract: A method and apparatus for growing truly bulk In2O3 single crystals from the melt, as well as melt-grown bulk In2O3 single crystals are disclosed. The growth method comprises a controlled decomposition of initially non-conducting In2O3 starting material (23) during heating-up of a noble metal crucible (4) containing the In2O3 starting material (23) and thus increasing electrical conductivity of the In2O3 starting material with rising temperature, which is sufficient to couple with an electromagnetic field of an induction coil (6) through the crucible wall (24) around melting point of In2O3. Such coupling leads to an electromagnetic levitation of at least a portion (23.1) of the liquid In2O3 starting material with a neck (26) formation acting as crystallization seed. During cooling down of the noble metal crucible (4) with the liquid In2O3 starting material at least one bulk In2O3 single crystal (28.1, 28.2) is formed.

Abstract: An interface circuit to the output of a programmable voltage ramp generator for decreasing the minimum voltage step of such a generator having two voltage channels and a minimum voltage step greater than 1 millivolt. The interface circuit receives an input from each of the two voltage channels (V.sub.2, V.sub.3), along with an inserted voltage (V.sub.1). The circuit includes a summing amplifier for (i) compressing the minimum voltage step from one voltage channel (V.sub.2) by a factor equal to or greater than such minimum voltage step, (ii) adding the voltage from the other channel (V.sub.3) to the compressed voltage, and (iii) subtracting the inserted voltage (V.sub.1) (or adding an inserted voltage which is negative). The inserted voltage (V.sub.1) is equal in magnitude to the maximum output value from the voltage channel that has the voltage compressed (V.sub.2). The output of the summing amplifier (V.sub.out) may be represented by:V.sub.out =(V.sub.3 /X)+(V.sub.2 /Y)+(V.sub.

Abstract: Undoped GaAs single crystals with low dislocation density, low impurity content, 0.20-1 Kg in weight and constant diameter of 1"-2" (inches), said single crystals being obtained with LEC technology at low or high pressure with synthesis of the polycrystal in situ and subsequent growth of the single crystal.