Modification of carrier localization in basal-plane stacking faults: The effect of Si-doping in a -plane GaN
Modification of carrier localization in basal-plane stacking faults: The effect of Si-doping in a -plane GaN
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基面堆垛层错中载流子局域化的修改：a 面 GaN 中硅掺杂的影响
DOI：
10.1002/pssb.201100480
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
Badcock T
中科院分区：
文献类型：
--
作者：
Badcock T
研究了在蓝宝石衬底上生长的Si掺杂平面GaN外延层的光学性质。在整个研究的掺杂范围内（1 × 1017至5 × 1019 cm −3），低温发射主要由基面堆垛层错（BSF）复合主导。从温度相关的光致发光（PL）测量结合PL激发研究，BSF中的载流子局域化能量被推断为随着掺杂密度从1 × 1017增加到5 × 1018cm−3而从17 meV降低到可以忽略的水平。有人提出，在生长温度下从Si施主原子电离的电子能够转移到BSF，在那里它们逐渐填充局域态的可用密度。对于超过1 × 1018cm−3的掺杂水平，发光线宽显著加宽，发光瞬态以单一指数时间常数衰减。这种行为归因于带填充的开始，其导致BSF内的自由电子密度显著增加。
The optical properties of Si‐dopeda‐plane GaN epilayers grown onr‐plane sapphire are studied. The low temperature emission is dominated by basal‐plane stacking fault (BSF) recombination throughout the investigated doping range (1 × 1017to 5 × 1019cm−3). From temperature dependent photoluminescence (PL) measurements in conjunction with PL excitation studies, the carrier localization energy within the BSF is inferred to decrease from 17 meV to a negligible level as the doping density increases from 1 × 1017to 5 × 1018cm−3. It is proposed that electrons, ionized from the Si‐donor atoms at the growth temperature, are able to transfer to the BSFs, where they progressively fill the available density of localized states. For doping levels in excess of 1 × 1018cm−3, the luminescence linewidth broadens significantly and the luminescence transients decay with a single exponential time constant. This behaviour is attributed to the onset of band‐filling which causes a marked increase in the free electron density within the BSFs.