Design and epitaxy of high Al-content AlGaN-based quantum structures and their applications for UV LEDs

深紫外LEDs在照明、印刷、杀菌消毒、环境保护、以及非视距军事保密通信等方面都有重大的应用价值和广泛的市场前景。经过研究者们多年的不断努力，AlGaN紫外LEDs虽然取得了大幅度进展，但由于高Al组分AlGaN结构材料存在着外延困难、缺陷密度高、强极化、掺杂激活难、正面出光少等科学和技术难题，其发光功率和效率与高亮度可见光LEDs相比还远不能令人们满意，波长短于300nm的深紫外LEDs的发光效率普遍较低。本论文采用MOVPE外延技术，结合材料的结构和性能表征以及第一性原理计算模拟方法，对高Al组分AlGaN材料外延和电导控制，以及紫外LEDs有源层结构设计、外延生长、器件制备等开展了系统研究...AlGaN-based deep-UV light-emitting diodes (DUV LEDs) have enormous potential for a wide range of applications, such as in illumination, printing, sterilization, water purification, medicine and biochemistry, and so on. Despite substantial progress has been made, the optical power and efficiency of DUV LEDs, especially with wavelengths shorter than 300 nm, is relatively lower than that of InGaN-bas...学位：理学博士院系专业：物理与机电工程学院_凝聚态物理学号：1982008015050

Emission Mechanism of High Al-content AlGaN Multiple Quantum Wells

紫外LED的发光功率和效率还远不能令人们满意,波长短于300 nm的深紫外LED的发光效率普遍较低。厘清高Al组分Al Ga N多量子阱结构的发光机制将有利于探索改善深紫外LED的发光效率的新途径、新方法。为此,本文通过金属有机气相外延技术外延生长了表面平整、界面清晰可辨且陡峭的高Al组分AlGa N多量子阱结构材料,并对其进行变温光致发光谱测试,结合数值计算,深入探讨了Al Ga N量子阱的发光机制。研究表明,量子阱中具有很强的局域化效应,其发光和局域激子的跳跃息息相关,而发光的猝灭则与局域激子的解局域以及位错引起的非辐射复合有关。The quantum efficiency of deep UV light emitting diodes( LED) drops dramatically with the increasing of Al content. Understanding the emission mechanism of high Al-content Al Ga N multiple quantum wells( MQW) is the one of the most important objects for improving the quantum efficiency of deep UV LED. In this work,high Al-content Al Ga N MQW structure with atomically flat hetero-interfaces was grown and characterized by photoluminescence( PL) measurements at different temperatures. The results indicate that there is a strong exciton-localization effect in the MQW structure and the emission is closely related to the hopping of the excitons. Due to the exciton delocalization and nonradiative recombination at defects,the PL intensity is strongly quenched at high temperatures.“973”国家重点基础研究发展计划(2012CB619300);; “863”国家高技术研究发展计划(2014AA032608);; 国家自然科学基金(U1405253;61227009;11204254;11404271);; 福建省自然科学基金(2015J01028)资助项

Preliminary pharmacodynamic study of STS as an adjuvant ofthe chemotherapy drugs in Vitro and in Vivo

目的：研究硫代硫酸钠（STS）是否能在体内、外作为化疗药的辅药。方法：应用MTT法研究STS分别与AdM、MMC和CddP等6种抗癌单药合用时对bEl-7402和MgC80-3细胞的细胞毒性作用；应用小鼠肝癌腹水瘤（H22）模型判断STS与AdM等3种药合用时的抗癌疗效；20例人原发性肝癌病人肝动脉插管化疗（AdM、MMC和CddP）前30MIn静脉推注STS（125~25g/M2）考察STS作为化疗药辅药的作用。结果：除了CddP以外，STS（500μg/Ml）与AdM等5种抗癌单药合用时对抗癌药的抗肿瘤细胞活性无明显影响（P＞005）。当不同剂量STS（350Mg/kg、35Mg/kg）分别与AdM（6Mg/kg）、MMC（14Mg/kg）和CddP（45Mg/kg）合用或仅这3种化疗药合用时，这3组腹水瘤小鼠的存活期比对照组者显著延长（P＜0001），但3组之间无明显区别（P＞005）。人肝癌肝动脉插管化疗时，STS与AdM、MMC和CddP抗癌药合用，肝癌治疗总有效率达60%，且可减少70%病人的恶心、呕吐等副作用。结论：在体内，低浓度的STS（125~25g/M2）可与AdM，MM？Objective: To study whether sodium thiosulfate (STS) can be used as an adjuvant of the chemotherapy drugs. Methods: The cytotoxicity of STS combined with ADM, MMC, CDDP, 5Fu, MTX and VCR (1PPC/ml) respectively on the cells of BEL7402 and MGc803 was studied by MTT test in vitro.The ascitic hepatoma (H22) in mice were adopted to determine the anticancer effect of STS adjuvant of ADMMMC and CDDP.Being treated with STS(12525 g/m2) 30 min before drug administration,20 patients of hepatocellular carcinoma (HCC) were carried on transcatheter arterial chemoembolization with ADMMMC and CDDP to observe the adjuvant effect of STS. Results: The anticancer activity of ADM and the other agents respectively adjuvant with STS (500 g/ml) were not obviously influented (P >005), but that for CDDP was influented .It was proven that the survival time of ascitic hepatoma treated with ADM (6 mg/kg),MMC (14 mg/kg) and CDDP (45 mg/kg) alone or three drugs in addition to STS (350 mg/kg,35 mg/kg) respectively was not significantly different (P >005).The survival time of each groups was significantly longer than that of control group (P< 0001).It have also been proven that STS adjuvant of ADM, MMC and CDDP was not decreased the chemotherapry effect (RR=60%) by transcatheter arterial chemoembolization in HCC, simultaneously it alleviated the nausea and vomiting in 70%patients. Conclusion: The study provides evidence that in vivo, STS (12525 g/m2) can be used as an adjuvant of chemotherapy drugs,such as ADM,MMC, including CDDP, and so on , for decreasing nausea and vomiting effects, espacially for transcatheter chemotherapy .福建省“八五”肝癌攻关课

Relieving EFFect of Sodium ThiosulFate on Transarterial Chemotherapic Emeses

报告硫代硫酸钠（STS）对20例肝动脉导管介入化疗病人的止呕辅助作用。通过体外琥珀酸脱氢酶抑制法（MTT）研究STS（500μg/Ml）辅助阿霉素（AdM）、丝裂霉素C（MMC）、顺铂（CddP）等7种抗癌药的抗肿瘤敏感试验，STS辅佐抗癌药的抗肿瘤活性无明显降低（P＞0·05），CddP除外。临床上，对肝癌病人经皮肝动脉插管化疗前30MIn静脉注射STS（1.25~2.50g/M2）或肌内注射灭吐灵（0.4Mg/kg）进行比较，观察两组病人呕吐的程度并进行统计分析。结果表明：STS比灭吐灵更能降低呕吐发生率而不影HCC的化疗效果。值得进一步研究STS辅佐其它化疗药的抗肿瘤作用，以及它在肿瘤化疗中的应用价值。It was reported that sodium thiosulFate (STS) was contributed to antivomiting eFFect in 20 transarterial chemotherapic patients.The antitumor sensitivity of STS (0.05 ) except For CDDP clinically,to comparing the adjuncting eFFects of STS (iv.30min ahead) or metoclopramdum (im.30min ahead) to ADM、MMC and CDDP on HCC(40 cases),the degrees of vomiting in hepatoma patient aFter transcatheter arterial chemoem bolization with ADM、MMC and CDDP were statisticaly analysed.It have been proven that STS was contributed to the low incidence of vomiting and superior to metocloe pramidum,without worsening of the chemotherapry of HCC.It is worth Futher studying adjuvant STS to other antitumor drungs and exploring potential application of chematherapy in cancer

Development of high Al content structural Ⅲ nitrides and their applications in deep UV-LED

随着高gA组分Ⅲ族氮化物相关研究的日趋深入和生长技术的日益成熟,人们逐渐将研究重心转向具有更宽带隙的高Al组分Ⅲ族氮化物。该材料常温下带隙宽至6.2 EV,可覆盖短至210 nM的深紫外波长范围,具有耐高温、抗辐射、波长易调控等独特优点,因而是制备紫外发光器件的理想材料。目前,高Al组分Ⅲ族氮化物材料质量不高,所制备的深紫外lEd发光器件仍存在内量子效率、载流子注入效率和沿C轴方向正面出光效率较低的难题,因而制约了高效紫外发光器件的制备。本文着重介绍了近年来在高Al组分Ⅲ族氮化物生长动力学方面的研究进展,总结和梳理了量子结构设计、内电场调控以及晶体场调控等方面的相关研究,以期实现高质量深紫外lEd的制备。Along with the extensive investigations and growth technology maturation on high Ga content III-nitrides,researchers have moved their focus onto high Al content III-nitrides.Given a wider band gap up to 6.2 eV at room temperature,covering UV-light area as short as 210 nm,as well as other advantages of III-nitrides,high Al content III-nitrides are ideal materials for the fabrication of UV-light emitting devices.At present,there are certain challenges in the fabrication of UV-light emitting devices with high internal quantum efficiency,carrier injection efficiency and light-extraction efficiency due to the low quality materials.In this work,the progress on growth kinetics of high Al content III-nitrides in recent years has been reviewed comprehensively,and the corresponding researches in quantum structure design,internal electric field modification and crystalline field modification have been overviewed and analyzed.This review is expected to be informative for the fabrication of deep UV-LEDs.“973”规划项目(2012CB619301、2011CB25600); “863”计划项目(2011AA03A111); 国家自然科学基金项目(61227009、90921002); 中央高校基本科研业务费专项资金资助项目(2012121014、CXB2011029); 福建省自然科学基金计划项目(2012J01024