Distribution of impurity elements between flux and melt during the growth of III-V compound semiconductor single crystals.

1.三族氧化物-B_2O_3二元系相图：在Ga_2O_3-B_2O_3和In_2O_3-B_2O_3系统中没有相图，在Al_2O_3-B_2O_3系统中只有一个相图。本文测定了三族氧化物(Ga_2O_3、In_2O_3、Al_2O_3)在B_2O_3熔体中的溶解度以及与熔体平衡的固相。利用这些数据高精度地绘制了Ga_2O_3-B_2O_3、In_2O_3-B_2O_3和Al_2O_3-B_2O_3二元系的相图。氧在液态镓和液态铟中的溶解度分别与固体Ga_2O_3或In_2O_3平衡的液态镓或液态铟中的氧的溶解度测定如下：log(O/质量%在液态镓中)=-6200/T+2.61(T：1123-1523K)log(O/质量%在液态铟中)=-6600/T+3.77(T：1073-137K)，氧在液态镓或液态铟中溶解的标准自由能变化可表示为：1/20O_2(G)=O(液态镓的质量%)，DELTAGﾟ=-2.45×10~(-5)+59.6T(J)1/20O_2(G)=O(液态铟的质量%)，DELTAGﾟ=-1.79×10~(^5)+33.8T(J)3.从基础研究的角度研究了三族金属氧化物(Ga_2O_3或In_2O_3)-B_2O_3二元熔剂与液态三族金属(Ga或In)之间的氧分配。测定了1423K时Ga系和第1373~1473K时In系中氧的分配比。在B_2O_3熔剂中，Ga_2O_3和In_2O_3的活度很小，这表明LEC过程中III-V化合物熔体中的氧含量可能被抑制到较低的水平。

1. Phase diagrams of III group oxide-B_2O_3 binary systems.No phase diagrams has been reported in Ga_2O_3-B_2O_3 and In_2O_3-B_2O_3 systems, and one phase diagram in Al_2O_3-B_2O_3 system. In the present work, solubility of III group oxide (Ga_2O_3, In_2O_3, Al_2O_3) in B_2O_3 melt and the solid phase equilibrated with the melt were determined. The phase diagrams of Ga_2O_3-B_2O_3, In_2 O_3-B_2O_3, and Al_2O_3-B_2O_3 binary systems were constructed with high accuracy using these data.2. Oxygen solubility in liquid gallium and liquid indium.The oxygen solubility in liquid gallium or liquid indium equilibrated with solid Ga_2O_3 or In_2O_3, respectively was determined as follows :log (O/mass% in liquid gallium) =-6200/T+2.61 (T : 1123-1523 K)log (O/mass% in liquid indium) =-6600/T+3.77 (T : 1073-1373 K)Using the temperature dependence of the oxygen solubility, the standard free energy change for oxygen dissolution in liquid gallium or liquid indium could be represented as follows :1/20O_2 (g) =O (mass% in liquid gallium) , DELTAGﾟ=-2.45x10^5+59.6T (J)1/20O_2 (g) =O (mass% in liquid indium) , DELTAGﾟ=-1.79x10^5+33.8T (J)3. Oxygen distribution between flux and meltOxygen distribution between III group metal oxide (Ga_2O_3 or In_2O_3) -B_2O_3 binary flux and liquid III group metal (Ga or In) was investigated in the view point of fundamental study for LEC method. Distribution ratio of oxygen for the Ga system at 1423 K and the In system at 1373 to 1473 K were determined. The activity of Ga_2O_3 and In_2O_3 in B_2O_3 flux were found to be small, which suggested that oxygen content in III-V compound melts might be suppressed to be lower level in the LEC process.