改进的锗浓缩技术及其生物传感器件

发布时间：2018-03-06 15:19

本文选题：绝缘体上锗　切入点：锗浓缩　出处：《兰州大学》2016年博士论文　论文类型：学位论文

【摘要】：“后22nm”时代,CMOS技术将从新型器件结构和新型沟道材料两方面来解决传统硅CMOS面临的问题。根据国际半导体技术发展路线图(ITRS),沟道材料将在15纳米的节点后逐步由应变硅材料过渡到新型高迁移率Ge/III-V半导体材料。绝缘体上锗(GOI)作为一种新型高迁移率衬底材料,结合了Ge材料高迁移率和SOI衬底CMOS兼容的优势,有望逐步成为主要的沟道材料。除应用于高速CMOS器件,GOI还在III-V基高速光电探测器、太阳能电池等方面具有更佳表现。锗浓缩技术是最常用也是最有望实现大规模生产超薄GOI的制备方法之一。然而由于传统锗浓缩过程中,SiGe/SOI界面的失配位错会逐步向上穿透,形成很高的缺陷密度(TDD107cm-2),影响最终器件性能。本论文正是在上述背景下,结合“极大规模集成电路制造设备及成套工艺”国家科技重大专项“新型混晶SOI与GOI高迁移率器件工艺开发”课题,开展了深入细致的探索和研究工作,本文的主要内容如下:1、提出改进的锗浓缩技术,并成功制备了8英寸高迁移率GOI衬底晶圆片。由传统的对SiGe/SOI进行浓缩改为直接对SGOI进行浓缩,得到高质量的GOI衬底材料。测试结果表明,所得GOI衬底具有低的表面粗糙度(1nm)和良好的结晶质量;缺陷密度相较于传统浓缩方法降低了近两个数量级(由1×107cm-2降低至7×105cm-2)。研究了浓缩过程中缺陷产生的机制,经测试分析,认为层间失配位错密度降低和应力释放是缺陷密度降低的主要原因。浓缩制备方法、材料表征以及性能分析详见第二章。2、在制备的GOI衬底上成功制备了Pseudo-MOSFET和源/漏肖特基器件,研究GOI材料的高迁移率特性及其在MOSFET器件中的应用。将改进型的30nm超薄GOI材料作为衬底制备了背栅结构的Pseudo-MOSFET器件,利用CMOS工艺制备了器件,所获器件的驱动电流相较于传统GOI材料提高了一倍。利用“Y值法”分析得出空穴迁移率为280cm2/Vs,相较于传统工艺GOI材料提高了56%。利用低温CMOS工艺、Al2O3和HfO2作为栅介质,制备了正栅结构的肖特基源/漏结GOI pMOS器件,研究了器件的高迁移率特性,所获器件的驱动电流相较于相同结构的SOI器件提高了约100倍。器件制备过程和器件特性分析详见第三章。3、利用锗浓缩技术与CMOS工艺,制备出了高质量、长度直径可控的Ge-SiO2“核-壳”结构纳米线阵列,设计制作了可实时检测、高灵敏度的生物传感器件。通过对纳米线表面功能化修饰,器件可以有效地分辨不同的pH值。将此器件进一步用于DNA杂交检测,发现其具有极高的灵敏度,理论响应极限达到5fM;对DNA杂交过程进行特异性检测,可以有效分辨碱基完全匹配、一个错配及完全错配等不同情况,具有极高的检测特异性。对DNA目标物浓度、溶液离子浓度以及DNA探针浓度等参数进行优化,检测极限提高到了0.5fM。纳米线制备、生物传感器制备、检测方法及传感特性详见第四章。
[Abstract]:In the "post-22nm" era, CMOS technology will solve the problems faced by traditional silicon CMOS from two aspects: new device structure and new channel material. According to the international semiconductor technology development roadmap, the channel material will be gradually formed after 15 nanometers of nodes. The strained silicon material is transitioned to a new type of high mobility Ge/III-V semiconductor material. Germanium on insulator is used as a new type of high mobility substrate material. Combining the advantages of GE material with high mobility and CMOS compatibility with SOI substrate, it is expected to gradually become the main channel material. Besides its application in high speed CMOS devices, it can also be used in III-V based high speed photodetectors. Germanium enrichment is one of the most commonly used and promising methods to produce ultra-thin GOI in large scale. However, the mismatch of SiGe / SOI interface will gradually penetrate upward in the traditional process of GE concentration. A high defect density (TDD107cm-2) is formed, which affects the performance of the final device. Combined with the project of "process development of new type mixed-crystal SOI and GOI high mobility device", the research work was carried out deeply and meticulously, according to the topic of "maximum scale integrated circuit manufacturing equipment and complete process", which is a major national science and technology project. The main contents of this paper are as follows: 1. An improved germanium enrichment technique is proposed, and an 8-inch high mobility GOI substrate wafer has been successfully prepared. High quality GOI substrates were obtained. The results show that the obtained GOI substrates have a low surface roughness of 1 nm) and good crystallization quality. The defect density is reduced by nearly two orders of magnitude (from 1 脳 10 7 cm -2 to 7 脳 10 5 cm ~ (-2)) compared with the traditional concentration method. The mechanism of defect generation in the process of concentration is studied and tested. It is considered that the decrease of interlaminar mismatch dislocation density and stress release are the main reasons for the decrease of defect densities. The preparation method of concentration, characterization of materials and analysis of properties are described in Chapter 2. The Pseudo-MOSFET and source / drain Schottky devices have been successfully fabricated on the prepared GOI substrates. The high mobility characteristics of GOI materials and their applications in MOSFET devices were studied. The modified 30nm ultra-thin GOI materials were used as substrates to fabricate Pseudo-MOSFET devices with back-gate structure, and CMOS process was used to fabricate the devices. The driving current of the obtained device is twice as high as that of the traditional GOI material. By "Y value method", the hole mobility of 280 cm ~ 2 / V _ s is obtained, which is 56% higher than that of the traditional GOI material. The low temperature CMOS process is used as the gate dielectric for Al _ 2O _ 3 and HfO2. Schottky source / drain junction GOI pMOS devices with positive gate structure have been fabricated and their high mobility characteristics have been studied. The driving current of the obtained device is about 100 times higher than that of the SOI device with the same structure. The fabrication process of the device and the analysis of the device characteristics are described in Chapter 3. The high quality of the device is obtained by using the germanium concentration technology and the CMOS process. A Ge-SiO2 "core-shell" nanowire array with controllable length and diameter was designed and fabricated for real-time detection and high sensitivity. The device can effectively distinguish different pH values. Further application of the device to DNA hybridization shows that it has a very high sensitivity and the theoretical response limit is up to 5fM. The specific detection of DNA hybridization process is carried out. It can effectively distinguish different cases such as base perfect matching, one mismatch and complete mismatch, and has very high detection specificity. The parameters such as DNA target concentration, solution ion concentration and DNA probe concentration are optimized. The detection limit is raised to 0.5fM.The preparation of nanowires, biosensors, detection methods and sensing characteristics are described in Chapter 4th.
【学位授予单位】：兰州大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TP212.3;TN304.11

【参考文献】