ENERGY FORMATION OF ANTISITE DEFECTS IN DOPED SB2TE3 AND BI2TE3 CRYSTALS
ENERGY FORMATION OF ANTISITE DEFECTS IN DOPED SB2TE3 AND BI2TE3 CRYSTALS
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DOI：
10.1016/0022-3697(86)90010-7
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发表时间：
1986-01-01
影响因子：
4
通讯作者：
KOUDELKA, L
中科院分区：
文献类型：
--
作者：
HORAK, J;CERMAK, K;KOUDELKA, L
用霍尔常数测定了Sb2−xInxTe3、Bi2−xInxTe3和Bi2Te3−xsx3晶体的自由载流子浓度，用等离子体共振频率计算了Sb2−xtlxte3晶体的自由载流子浓度；随着x值的增大，孔洞浓度减小。由于在sb2te3和Bi2Te3晶格中分别掺入了In、Tl和S元素，从而产生了InxSb、TlxSb、InxBiand SxTe等未带电缺陷，导致了反位缺陷浓度的降低。这个已证明的效应可以用以下方式解释：反位缺陷只能在原子被弱极化键束缚的晶体中产生。在sb2te3或bi2te3的晶格中加入In、Tl和S原子增加了键极性，三元晶体的离子性增加。这不利于反位缺陷的增加，反位缺陷的浓度降低。键极性的变化可以从上述三元晶体反位缺陷形成能的变化来考虑。
The free carrier concentration of the Sb2−xInxTe3, Bi2−xInxTe3and Bi2Te3−xSxcrystals has been determined from the values of the Hall constants and the free carrier concentration of the Sb2−xTlxTe3has been calculated from the plasma resonance frequency; with increasing value ofx, the hole concentration decreases. As the incorporation of the elements In, Tl and S into the lattice Sb2Te3or Bi2Te3, respectively, gives rise to the uncharged defects InxSb, TlxSb, InxBiand SxTe, thexcauses the decrease of the antisite defects concentration. The proven effect is explained in the following way: the antisite defects can be created only in crystals whose atoms are bound by weakly polarized bonds. The incorporation of In, Tl and S atoms into the crystal lattice of Sb2Te3or Bi2Te3increases the bond polarity, the ionicity of ternary crystals increases. This unfavorably affects the increase of antisite defects whose concentration decreases. The change of the bond polarity is considered from the changes discovered in the formation energy of antisite defects of the above mentioned ternary crystals.