Wahl U, Rita E, Correia J G, Marques A C, Alves E, Soares J C
Instituto Tecnológico e Nuclear, Estrada Nacional 10, 2686-953 Sacavém, Portugal.
Phys Rev Lett. 2005 Nov 18;95(21):215503. doi: 10.1103/PhysRevLett.95.215503. Epub 2005 Nov 15.
Arsenic has been reported in the literature as one of the few p-type dopants in the technologically promising II-VI semiconductor ZnO. However, there is an ongoing debate whether the p-type character is due to As simply replacing O atoms or to the formation of more complicated defect complexes, possibly involving As on Zn sites. We have determined the lattice location of implanted As in ZnO by means of conversion-electron emission channeling from radioactive (73)As. In contrast to what one might expect from its nature as a group V element, we find that As does not occupy substitutional O sites but in its large majority substitutional Zn sites. Arsenic in ZnO (and probably also in GaN) is thus an interesting example for an impurity in a semiconductor where the major impurity lattice site is determined by atomic size and electronegativity rather than its position in the periodic system.
在文献中，砷被报道为技术上有前景的II-VI族半导体氧化锌（ZnO）中少数几种p型掺杂剂之一。然而，关于p型特性是由于砷简单地取代氧原子，还是由于形成了更复杂的缺陷复合体（可能涉及锌位点上的砷），目前仍存在争议。我们通过放射性（73）砷的转换电子发射沟道技术确定了氧化锌中注入砷的晶格位置。与从其作为第V族元素的性质所预期的情况相反，我们发现砷并不占据替代氧位点，而是在绝大多数情况下占据替代锌位点。因此，氧化锌（可能还有氮化镓）中的砷是半导体中杂质的一个有趣例子，其中主要杂质晶格位点由原子大小和电负性决定，而非其在周期表中的位置。
