Dynamics of bound-exciton luminescences from epitaxial GaN
Dynamics of bound-exciton luminescences from epitaxial GaN
复制标题
外延 GaN 束缚激子发光的动力学
DOI：
10.1063/1.116703
复制
发表时间：
1996
影响因子：
4
通讯作者：
P. Baranov
中科院分区：
文献类型：
--
作者：
L. Eckey;J. Holst;P. Maxim;R. Heitz;A. Hoffmann;I. Broser;B. Meyer;C. Wetzel;E. N. Mokhov;P. Baranov
用时间积分和时间分辨的光致发光测量方法研究了用升华技术在6H-SiC衬底上生长的GaN外延层的自由和束缚激子发光。对3.4722 eV的施主束缚激子和3.4672 eV和3.459 eV能量的两个受主束缚激子的寿命进行了测定。在此基础上，我们得到了GaN的自由激子振子强度上限为0.0046。在3.29 eV到3.37 eV之间的发光是由于激子深深束缚在衬底-外延层界面附近的中心。自由激子在20ps内被这些中心捕获。
Free‐ and bound‐exciton luminescences of GaN epitaxial layers grown by a sublimation technique on 6H‐SiC substrates were investigated using time‐integrated and time‐resolved photoluminescence measurements at low temperatures. Lifetimes were determined for the donor‐bound exciton at 3.4722 eV and for two acceptor‐bound excitons with energies of 3.4672 eV and 3.459 eV. On the basis of our results we obtain an upper limit of the free‐exciton oscillator strength of 0.0046 for GaN. Luminescences between 3.29 eV and 3.37 eV are identified as due to excitons deeply bound to centers located near the substrate‐epilayer interface. Free excitons are captured by these centers within 20 ps.