Development of High Quality and Low Defect Density Semi-polar and Non-polar GaN Templates

来源 :第十届中国国际半导体照明论坛 | 被引量 : 0次 | 上传用户:liongliong502
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
  Today commercially available wurtzite nitride based visible optoelectronic devices [1],grown along the polar [0001] c-direction,suffer from the presence of polarization-related electric fields inside multiple-quantum wells (MQWs).The discontinuities in both spontaneous and piezoelectric polarization at the hetero-interfaces result in internal electric fields in the quantum wells which causes carrier separation (quantum confined Stark effect (QCSE) and reduces the radiative recombination rate within quantum wells (QWs) [2–5].This effect is particularly strong in high indium content devices such as green emitters,hence the very poor efficiency performance to date of direct green emitting devices.To decrease these polarization effects,devices have been grown on the non-polar and semi-polar planes.These have attracted significant attention because not only can they improve device efficiency in blue and violet devices but also,more significantly,they enable the development of high efficiency green emitters.To date,however,high quality non-polar or semi-polar GaN material has only been available through cutting expensive bulk GaN boules at the appropriate angle.Unfortunately,this method only yields small pieces,typically up to 10 mm by 15 mm,which are only suitable for fundamental research.Conventional ELOG (epitaxial lateral over growth) has also been employed to improve the crystal quality of non-polar and semi-polar GaN grown on sapphire substrates,however,the non-uniformities associated with this method along with the thick overgrowth (5 – 10 μm) needed to coalesce the layer makes this unsuitable as a route to commercialization of non-polar and semi-polar GaN.This paper presents the results of high quality and cost effective non-polar and semi-polar GaN templates on sapphire,employing unique nanotechnology developed by Seren Photonics and the University of Sheffield [6,7].
其他文献
一、引言天线的几何形状尺寸和频率决定了天线的等效电性能的参数。便携式车载式短波电台通常都选用容性天线。天线回路调谐的目的,就是调整天线电流达最大值并将谐波电流分
“九五”时期,浙江以民间投资为主体的非国有投资累计完成5954亿元,比“八五”增长1.88倍,占全社会投资的比重平均达64%,居全国之首。特别是2000年,非国有投资完成1391亿元,
汽车轻量化已经成为提高汽车产品竞争力以及推动汽车行业节能减排的主要手段之一,随着轻量化需求的不断提高,高强度钢和铝合金在车身上的应用越来越多,进而产生汽车车身用钢
本文根据原实际的生产状况提出改进设计方案,并通过对驾驶室内饰的工作原理及相关理论进行分析,经实际验证改进获得成功.改进后的设计方案不仅降低了劳动强度,而且大大地提高
目的 对比研究有限切开微型钢板与克氏针内固定治疗掌骨骨折的疗效.方法 选取2017年10月~2019年11月于我院就诊的掌骨骨折患者42例,随机分为观察组(21例)和对照组(21例),给予
2001年以来,农发行怀柔县支行在学习总行制定的《调销贷款管理办法》和分行有关规定的基础上,从转变观念入手,积极稳妥支持购销企业,按照“购得进,销得出,有效益”的原则发
任振奎(吉林省通化钢铁公司大栗子铁矿职工医院)报道:自1973年12月至1980年12月随机观察了63例接受计划治疗与68例未接受计划治疗的各期矽肺患者的升期及死亡情况。两组患者
初学摄像,往往对摄像机有种神秘感,以为一定很难学。可用过几次后,又会觉得很容易,比用照相机还容易。的确,摄像机做为高科技产品,自动化程度较高,尤其是家用型,小巧玲珑,操
广大读者及广告客户:首先,非常感谢您们多年来对我刊的厚爱!经过20年的发展,我刊在全国农业期刊业内已具有较高的知名度和影响力。近期,在市场上发现了冒用《湖北植保》的报
3G无线网络建设中,城市无疑占据了最为重要的位置,不仅因为它涵盖了大量的移动用户群体,同时还因复杂的建筑物环境,对无线网络的建设提出了更高的挑战。 大 城 市上海贝尔