【作者】 朱海；

【导师】 姚斌； 单崇新；

【作者基本信息】 中国科学院研究生院（长春光学精密机械与物理研究所） ， 凝聚态物理， 2011， 博士

【摘要】 ZnO材料由于具有宽带隙(3.37 eV),大的激子束缚能(60 meV)等优点,在紫外发光二极管、半导体激光器等方面具有广阔的应用前景。针对目前国际上ZnO电泵浦激光研究方面的不足以及MgZnO材料深紫外激光的研究空白。本论文采用原子层沉积技术、分子束外延技术、磁控溅射等方法制备了ZnO基紫外发光器件。实现了低阈值的ZnO随机激光输出及ZnO异质pn结电泵浦受激发射。此外,对深紫外波段的MgZnO电注入受激发射进行了初步的研究探索。取得的主要结果如下:(1)针对目前随机增益介质p型掺杂难以实现的问题,采用介电层碰撞离化产生的空穴为随机增益介质提供空穴的思想,构建了Au/MgO/ZnO结构器件。室温条件下在该结构中获得了阈值电流为43 mA的ZnO随机激光输出。为了降低随机激光的阈值电流,通过引入绝缘ZnO层作为空穴产生层,降低了电子-空穴对的离化阈值,成功的将激光发射阈值电流降低到了6.5 mA。(2)针对目前MgZnO材料p型和n型有效掺杂难以实现的问题,我们采用MgO层碰撞离化产生的空穴为MgZnO发光层提供空穴载流子,同时利用n型ZnO为MgZnO发光层提供电子的思想,实现了MgZnO材料波长在330 nm附近的电泵浦激光发射。利用组分渐变MgxZn1-xO梯度势垒层来提高载流子注入的思路,在立方相MgZnO中首次实现了波长在276 nm的深紫外电注入发光。(3)采用介电层调节载流子输运的思想,克服了直接匹配型ZnO异质pn结中存在的ZnO发光较弱问题,达到电子和空穴在ZnO发光层同时富集的目的。在p-GaN/MgO/n-ZnO结构中实现了阈值电流为0.8 mA的受激发射。进而尝试将ZnO替代为带隙更大的MgZnO材料,获得了波长在374 nm附近的激子型电致发光。更多还原

【Abstract】 ZnO possesses unique figures of merits for application in ultraviolet (UV) light emitting diode, semiconductor laser and photodetectors, such as large band gap (3.3 eV), large exciton binding energy (60 meV). For the problem of the electronically pump ZnO lasing and the absence of lasing from MgZnO currently. In this thesis, we fabricated ZnO-based UV light emitting devices by atom layer deposition, molecular beam epitaxy and radio-frequence magnetic sputtering. We realized low-threshold current ZnO random laser operation and ZnO pn heterojunction electrically pump lasing. In addition, we try to research the electrically pump the deep ultraviolet lasing based on MgZnO preliminarily. The main results were obtained as follows:(1) For the problem of the p type doping of the random gain materials currently, we make use of the method of dielectric impact the hole for the random gain materials. Based on this method we form the Au/MgO/ZnO MOS structure. At room temperature, the random lasing from ZnO with the threshold current 43 mA was obtained. For decrease the threshold current in laser devices. We take use the insulator ZnO, this insulator ZnO layer can decrease the generation threshold of holes carriers. Cosequentlly, the threshold current of the device was decreaseed to 6.5 mA successfully. (2) For the problem of that the efficiency p type and n type doping of MgZnO material is realized difficultly. We make use of the idea that the MgO impact the hole for the MgZnO active layer and use the n-ZnO supplies the electrons for the MgZnO active lasyer. The electronically pumped lasing with the emission wavelength of 330 nm from MgZnO was demonstrated. By use the idea that the grade component of MgxZn1-xO layer for increase the electron injection, the deep UV LED with the emission wavelength of 276 nm was demonstrated in the cubic-MgZnO firstly.(3) By use of the idea of dielectronic layer modulation carriers transport process for overcome the problem of low emission intensity from ZnO in the ZnO-based heterojuction pn devices and realize the purpose of electrons and holes accumulate in ZnO active layer. A lasing with the low threshold current of 0.8 mA was realized in the p-GaN/MgO/n-ZnO structure. In addition, instead the ZnO with the MgZnO material, the exciton type ultraviolet light emitting devices with the wavelength of 374 nm was demonstrated.更多还原