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在氢气氛中使乙硼烷与磷化氢混合料热分解和在氢气中加热还原三溴化硼与三氯化磷混合料,已经在六角晶型的碳化硅基面上淀积起磷化硼。在热分解过程中,为把气相反应的影响减到最小,基底温度必须维持在900℃以下,此时,磷化硼层刚露出择优取向。热还原过程是在一个宽的温度区间内完成的;用光学显微镜和反射电子衍射观察发现,在1050℃—1150℃碳化硅表面上沉积的磷化硼层是单晶体,而且是按基底外延的。卤化物还原反应制备外延的磷化硼,无特意掺杂时是P型的,室温载流子浓度约为10~(19)cm~(-3)。在300—1000°K温度区间内电阻率的测量指出存在着两种杂质能级,它们的激活能分别约为0.22和0.66电子伏特。用卤化物还原反应也获得了针状磷化硼晶体,它们是长轴沿着<111>方向的P型单晶,在室温时电阻率约为20欧姆·厘米。
Pyrogenation of the diborane and phosphine mixture in a hydrogen atmosphere and the reduction of the mixture of boron tribromide and phosphorus trichloride in a hydrogen atmosphere by heating in a hydrogen atmosphere has been carried out on a hexagonal silicon carbide base by phosphating boron. In the thermal decomposition process, in order to minimize the influence of the gas phase reaction, the substrate temperature must be maintained below 900 ° C, at which point the boron phosphide layer has just been exposed to the preferred orientation. The thermal reduction was carried out over a wide temperature range. Observation by light microscopy and reflection electron diffraction revealed that the layer of boron phosphide deposited on the surface of the silicon carbide at 1050 ° C-1150 ° C was single crystal and epitaxial by substrate. The epitaxial boron phosphide is prepared by the halide reduction reaction, and is P type without any specific doping. The carrier concentration at room temperature is about 10-19 cm -3. The measurement of the resistivity in the temperature range of 300-1000 ° K indicates that there are two impurity levels with activation energies of about 0.22 and 0.66 eV, respectively. Needle-shaped boron phosphide crystals were also obtained by the halide reduction reaction. They are P-type single crystals with the major axis along the <111> direction and a resistivity of about 20 ohm.cm at room temperature.