论文部分内容阅读
以硼酸和三聚氰胺为原料,利用化学法、真空热处理及高温高压技术对BCN化合物的形成、结构及相变进行了研究.在真空10-3Pa条件下,经1273K高温热处理得到非晶B_C_N前驱物.这种前驱物在920K以下为绝缘体,在920K由绝缘体转变为非晶半导体.在973—1003K和1013—1073K范围这种非晶半导体表现出不同的电导_温度关系,电导激活能分别为0·34eV和1·10eV,表明在两个不同的温度区域这种非晶半导体的导电机构不同.将这种前驱物在3·5GPa,经1473K退火40min后由非晶态转化为单相六方结构的B_C_N晶体,其成分为B0·44C0·27N0·29,晶格常数为a=0·2515nm,c=0·6684nm.六方B0·44C0·27N0·29晶体在1330,1364,1588和1617cm-1出现四个强的Raman散射峰,其中1330和1617cm-1被认为是六方B0·44C0·27N0·29晶体特征Raman散射峰.
Using boric acid and melamine as raw materials, the formation, structure and phase transition of BCN compounds were studied by chemical method, vacuum heat treatment and high temperature and high pressure technology, and the amorphous B_C_N precursors were obtained by heat treatment at 1273K under vacuum of 10-3Pa. Such precursors are insulators below 920 K and from insulators to amorphous semiconductors at 920 K. Such amorphous semiconductors exhibit different conductance-temperature relationships in the 973-1003K and 1013-1073K ranges, with conductance activation energies of 0 · 34eV and 1 · 10eV, indicating that in two different temperature regions of this amorphous semiconductor conductive mechanism is different from this precursor at 3.5GPa, after annealing at 1473K 40min from the amorphous into a single phase hexagonal structure The B_C_N crystal has a composition of B0 · 44C0 · 27N0 · 29 and a lattice constant of a = 0 · 2515 nm and c = 0.6684 nm. The hexagonal B0 · 44C0 · 27N0 · 29 crystal appears at 1330, 1364, 1588 and 1617 cm-1 Four strong Raman scattering peaks, of which 1330 and 1617 cm-1 are considered to be characteristic Raman scattering peaks of the hexagonal B0 · 44C0 · 27N0 · 29 crystal.