Microscopic structure of the hydrogen-boron complex in crystalline silicon.
Microscopic structure of the hydrogen-boron complex in crystalline silicon.
复制标题
晶体硅中氢硼络合物的微观结构。
DOI：
--
复制
发表时间：
1989
期刊：
影响因子：
--
通讯作者：
S. Pantelides
中科院分区：
文献类型：
--
作者：
P. Denteneer;C. G. V. D. Walle;S. Pantelides
硅中氢-硼复合物的微观结构，这是由氢钝化掺硼硅引起的，在文献中有广泛的争论。大多数争论集中在H原子的平衡位置上。在这里，我们研究的复合物的微观结构，使用无参数的总能量计算和探索的整个能量表面的H在Si：B。我们最终表明，全球能量最小值发生在一个网站接近中心的Si-B键（BM网站）的H，但有一个障碍只有0.2 eV的四个等效BM网站之间的H原子的运动。这种低能量势垒意味着在室温下H能够围绕B原子移动。其他网站H提出的平衡网站被证明是鞍点相当高的能量。计算了H伸缩模在BM位的振动频率，结果与实验相符。讨论了配合物离解能的计算。
The microscopic structure of hydrogen-boron complexes in silicon, which result from the passivation of boron-doped silicon by hydrogen, has been extensively debated in the literature. Most of the debate has focussed on the equilibrium site for the H atom. Here we study the microscopic structure of the complexes using parameter-free total-energy calculations and an exploration of the entire energy surface for H in Si:B. We conclusively show that the global energy minimum occurs for H at a site close to the center of a Si-B bond (BM site), but that there is a barrier of only 0.2 eV for movement of the H atom between four equivalent BM sites. This low energy barrier implies that at room temperature H is able to move around the B atom. Other sites for H proposed by others as the equilibrium sites are shown to be saddle points considerably higher in energy. The vibrational frequency of the H stretching mode at the BM site is calculated and found to be in agreement with experiment. Calculations of the dissociation energy of the complex are discussed.