2英寸AlN自支撑衬底生长及应力和缺陷控制研究

项目名称： 2英寸AlN自支撑衬底生长及应力和缺陷控制研究

项目编号： No.61274127

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 无线电电子学、电信技术

项目作者： 张纪才

作者单位： 中国科学院苏州纳米技术与纳米仿生研究所

项目金额： 86万元

中文摘要： AlN衬底是制备高性能深紫外光电器件、高频大功率微波器件的关键基础材料。由于AlN具有键能大、原子扩散势垒高、位错形成能低和生长应力大等特点，目前制备大尺寸高质量AlN自支撑衬底仍是难题。本项目拟利用氢化物气相外延（HVPE）法具备的高生长速率和适合大尺寸单晶生长的优势，采用掩膜和侧向外延技术生长大尺寸AlN自支撑衬底。围绕上述思路，理论模拟与实验相结合，研究AlN厚膜制备过程中的应力起源及演变机理，解决HVPE快速生长过程中的应力控制问题；系统研究位错密度从1010cm-2降至106cm-2过程中, AlN外延层中的应变和缺陷演变机理，建立应变-缺陷耦合动力学模型；深入研究AlN中的深能级缺陷及其形成机理，探究降低其密度的有效途径；解决材料生长中的关键科学问题，掌握关键生长技术，获得位错密度为106cm-2的2英寸AlN自支撑衬底，为我国发展深紫外光电器件、高频大功率微波器件奠定基础。

中文关键词： HVPE；AlN/蓝宝石模板；AlN自支撑衬底；位错密度；

英文摘要： AlN is the critical and basic material for the fabrication of deep ultraviolet optoelectronic and high-frenquency high-power microwave devices. However, the fabrication of high-quality large-size AlN free-standing substrate is still very difficult due to the large bond energy, high barrier for atom diffusion, low energy of dislocation formation, and the large stress during the growth. The proposed project will use hydride vapor phase epitaxy（HVPE）to grow AlN free-standing substrate, which can provide high growth rate and be suitable for large-size single crystal growth. The special mask and epitaxial lateral overgrowth techniques will be used to obtain the high crystal quality and decrease the strain of epilayers. By the association of experimental result and theoretical simulation, the origin and development of stress in AlN thick epilayer will be studied deeply to control the strain during the high-speed HVPE growth. On the other hand, the evolution of strain and defect during the AlN growth when dislocation density changing from 1010cm-2 to 106cm-2 will be studied systematically to found the coupling kinetic model of strain-defect. The deep-level defects and their forming mechanism in AlN epilayer will also be studied to find the effective methods to decrease them. From this reaserch, the key scientific issue

英文关键词： HVPE；AlN/sapphire template；AlN free-standing substrate；dislocaiton density；