Carrier Compensation Mechanism in Wide Bandgap II-VI Semiconductors

Park等人和Ohkawa等人是第一个使用活性氮作为掺杂剂成功地掺杂通过MBE生长的ZnSe的人，并且这一重要步骤导致了第一个II-VI蓝-绿激光二极管的演示。然而，关键问题仍然是如何获得高电导率的p型材料和精确的空穴补偿机制。在这项研究中，在ZnSe：N已经通过高分辨率光谱、光致发光激发、选择性光致发光激发，在过去的几年中，已经发现氮是生产p-补偿的机制似乎是形成了这种结合能为57 meV的新型施主中心。深施主的证据来自于PL， ...更多信息 光谱从ZnSe：N与高浓度的N。另外，通过详细的光学研究，在高掺杂的ZnSe：N中发现了一个结合能为88 meV的施主和一个结合能为170 meV的受主。本文提出了N掺杂ZnSe的能量Lovel图，并从实验和理论上将补偿现象的原因归结为：（i）本征点缺陷的补偿（如在相邻Zn位（N_ -Zn-V_）上由N-受主和硒空位组成的施主型复合缺陷<Se><Se>）;（ii）N团簇的补偿（如在相邻Zn位（N_ -N_）上由N-受主和N原子组成的双施主<Se><Zn>）;（iii）间隙位（N_）上的N原子的补偿<int>;（iv）强的晶格弛豫。此外，氮可以形成深而不是浅的受主，如（N_<Se>-Zn-N_<Se>）。在光学研究中发现的深施主和受主中心的起源已被关联到这些N相关的复杂的缺陷，并提出。少

There has been a lomg history of attempts to achieve reliable p-type wide bandgap II-VI semiconductors Park et al.and Ohkawa et al.were the first to successfully dope ZnSe grown by MBE using active nitrogen as a dopant and this important step led to the first demonstration of II-VI blue-green laser diodes. IIowever, the key issue remains how to achieve high conductivity p-type materials and pinpoints the mechanism of hole compensation. In this study, the identification and characterization of impurity levels in ZnSe : N have been extensively made by means of high resolution spectroscopy, photoluminescent excitation, selective photoluminescent excitation, deep level spectroscopy.Over the past few years nitrogen has been found to be the best dopant in the production of p-type ZnSe by MBE.The mechanism of compensation appears to be the formation of this new type of donor center with a binding energy of 57meV.Evidence for the deep donor comes from the appearance of the DAP lines in the PL, … More spectra from ZnSe : N with a high N concentration. Additionally, a donor with a binding energy of 88meV and an acceptor with a binding energy of 170meV have been found in highly doped ZnSe : N through detailed optical studie. The energy lovel diagram has been proposed for N-doped ZnSe.The caues of the compensation phenomenon have been attributed experimentally and theoretically to a number of origins : (i) compensation by native point defects (eg.a donor-type complex defect consisting of an N-acceptor and a selenium vacancy on a next nearest neighbor site (N_<Se>-Zn-V_<Se>) ; (ii) compensation by N clusters, for instance, a double donor consisting of a N acceptor and a N atom on adjacent Zn site (N_<Se>-N_<Zn>) ; (iii) compensation by N atoms at interstitial sites (N_<int>) ; and (iv) strong lattice relaxation. In addition, the nitrogen could form deep instead of shallow acceptors such as (N_<Se>-Zn-N_<Se>). The origins of the deep donor and acceptor centers found in the optical studies have been correlated to these N-associated complex defects and proposed. Less