Highly n-doped silicon: Deactivating defects of donors
Highly n-doped silicon: Deactivating defects of donors
复制标题
高n掺杂硅：使施主缺陷失活
DOI：
10.1103/physrevb.70.245207
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发表时间：
2004
影响因子：
3.7
通讯作者：
W. Fichtner
中科院分区：
文献类型：
--
作者：
D. C. Mueller;W. Fichtner
我们报告洞察重掺杂硅中的基团供体的失活机制。基于ourab初始计算，我们提出了一个三步模型的施主失活。在低温下生长的highly-typegrown中，在没有多余的原生点缺陷的情况下，本征极限似乎部分地通过在两个或更多个施主原子附近共享接近位点的硅晶格的施主失活扭曲而上升。此外，供体二聚体在高掺杂浓度下的失活中起重要作用。虽然二聚体构成稳定或亚稳定的非活性施主配置，但晶格畸变使施主能级逐渐降低到简并硅中的杂质带以下。另一方面，我们发现，在一般情况下，没有早期提出的失活施主对缺陷是稳定的费米能级的任何位置。晶格畸变可以被视为Frenkel对生成和施主-空位聚集过程（步骤2）的前体，其解释了在升高的温度和较长的退火时间下的失活。最后，在大原子的情况下，最突出的是，施主原子的沉淀可能是失活过程链的最后一步。
We report insight into the deactivation mechanisms of groupdonors in heavily doped silicon. Based on ourab initiocalculations, we suggest a three step model for the donor deactivation. In highly-typegrown at low temperatures, in the absence of excess native point defects, the intrinsic limit toseems to rise in part by means ofdonor deactivating distortionsof the silicon lattice in the proximity of two or more donor atoms that share close sites. Also, donor dimers play an important part in the deactivation at high doping concentrations. While the dimers constitute a stable or metastable inactive donor configuration, the lattice distortions lower the donor levels gradually below the impurity band in degenerate silicon. On the other hand, we find that, in general, none of the earlier proposed deactivating donor pair defects is stable at any position of the Fermi level. The lattice distortions may be viewed as a precursor to Frenkel pair generation and donor-vacancy clustering process (step 2) that account for deactivation at elevated temperature and longer annealing times. Ultimately, and most prominently in the case of the largeatoms, precipitation of the donor atoms may set in as the last step of the deactivation process chain.