|Place of Conferral||北京|
|Keyword||双多晶自动准 双极晶体管 60co-γ辐射 基极 发射极尺寸 辐射损伤 Eldrs|
摘 要随着核科学和航天技术的发展，越来越多的半导体器件和集成电路及各种材料应用于空间领域的各种苛刻、复杂和恶劣辐射环境中，其性能必然受到辐射环境的影响而发生退化，给空间电子系统的可靠性带来极大隐患。而且双极器件的低剂量率辐射损伤增强效应(Enhanced Low Dose Rate Sensitivity, ELDRS)的存在，为其在空间中的应用又带来了新的难题。自从双极器件ELDRS效应发现以来，人们一直致力于完善其发生的内在物理机制，寻找高效可靠的加速评估方法，以及尝试各种措施来对双极器件进行抗辐射加固设计。双多晶自对准（Double Polysilicon Self-aligned, DPSA）双极器件便可以看作是从工艺结构上对双极器件抗辐射加固的一种设计尝试。由于DPSA双极晶体管的制备工艺和器件结构大大区别于传统工艺常规双极器件，故其在空间环境中的辐照响应也可能与传统工艺双极器件不同。因此，对国产DPSA工艺双极器件进行电离辐射效应研究及其损伤机理的分析具有重要意义。本文选用国产DPSA工艺制备的双极晶体管为实验样品，研究了其不同剂量率、不同基区个数和不同发射极尺寸对晶体管辐照损伤的影响，优化筛选出了抗辐照损伤能力最佳的工艺设计方案，进而为双极器件的抗低剂量率辐照加固提供了新的途径。文章主要研究工作如下：第一，研究了不同剂量率辐照时国产DPSA工艺双极晶体管的电离辐射效应。研究表明，国产DPSA工艺双极晶体管存在低剂量率辐照损伤增强效应，即低剂量率下相对于高剂量率表现出更为严重的辐照损伤，并结合双分子模型对DPSA工艺双极晶体管低剂量率辐照损伤增强效应的机理进行了分析。第二，研究了不同基区个数DPSA工艺双极晶体管的电离辐射效应。研究表明，DPSA工艺双极晶体管的电离辐照损伤程度与其基区个数存在一定的依赖关系，具体表现为单基区NPN晶体管抗辐照损伤能力整体上要强于双基区NPN晶体管。第三，研究了DPSA工艺双极晶体管相对于传统工艺双极晶体管表现出的抗辐照性能。研究表明，与传统工艺双极晶体管相比，DPSA工艺双极晶体管能够有效地提升器件的抗辐照损伤能力，并对该实验结果的内在机制进行了理论分析。第四，研究了不同发射极尺寸国产DPSA工艺双极晶体管的电离辐射效应。研究表明，DPSA工艺双极晶体管的辐照损伤程度与其发射极长度存在密切关系，具体表现为发射极长度越大的晶体管辐照损伤越严重。结合基区个数对DPSA双极晶体管辐照损伤的影响，进而优化筛选出了单基极结构且发射极长度为1.6um的NPN晶体管为抗辐照损伤能力最佳的工艺设计方案。
AbstractWith the development of nuclear science and space technology, more and more semiconductor devices and integrated circuits and a variety of materials have to be used in the field of space in a variety of harsh and complex radiation environment, and their performance must be affected by the radiation environment, which will induce a great potential risk to the reliability of space electronic systems. The existence of enhanced low dose rate sensitivity (ELDRS) of bipolar devices has brought new problems for the application in space. Since the discovery of the ELDRS effect of bipolar devices, people have been working to improve the inherent physical mechanism, to find efficient and reliable acceleration assessment methods, and to try various measures to radiation hardness design of bipolar devices. Double polysilicon self-aligned (DPSA) bipolar devices can be seen as a design attempt to radiation hardness from process structures of bipolar devices. As the DPSA bipolar transistor manufacture process and device structure are much different from the traditional process of conventional bipolar devices, the radiation response in the space environment may also be different from the traditional bipolar device. Therefore, it is very important to study the ionizing radiation effect of the DPSA bipolar device and its damage mechanism.In this paper, the bipolar transistors prepared by domestic DPSA process were selected as samples, and the ionizing radiation effect of bipolar transistor by domestic DPSA process with different radiation dose rates, different numbers of base regions and emitter geometric dimensions were studied. The optimal design method of anti - radiation damage ability is selected, which provides a new way for the anti - low dose rate irradiation of bipolar devices. The main research work is as follows:Firstly, the ionizing radiation effect of the DPSA bipolar transistor was studied at different radiation dose rates. The results show that the DPSA bipolar transistor has ELDRS that bipolar devices exhibit more severe radiation damage at low dose rate irradiation. The two-molecule model on the enhancement effect of low dose rate radiation damage was discussed.Secondly, the ionizing radiation effect of DPSA bipolar transistors in different number of base regions was studied. The results show that the degree of ionization radiation damage of DPSA bipolar transistor has a certain dependence on the number of its base regions. It is shown that the radiation hardness ability of NPN transistor with single base region is stronger than that of NPN transistor with double base region.Thirdly, the radiation hardness performance of DPSA bipolar transistor relative to traditional bipolar transistor is studied. The DPSA bipolar transistor can effectively improve the radiation hardness ability of the device compared with the traditional bipolar transistor. The internal mechanism of the experimental result is analyzed theoretically.Fourthly, the ionizing radiation effect of DPSA bipolar transistors with different emitter geometries was studied. The results show that the degree of radiation damage of DPSA bipolar transistor is closely related to its emitter length, and the larger the emitter length is, the more serious the radiation damage of transistors is. Combined with the influence of the number of base regions on the DPSA bipolar transistor irradiation damage, the NPN transistor with single base region structure and emitter length of 1.6um is optimized to optimize the process design for radiation hardness ability.
|贾金成. 基于国产双多晶自对准工艺的双极晶体管辐射效应研究[D]. 北京. 中国科学院大学,2017.|
|Files in This Item:|
|基于国产双多晶自对准工艺的双极晶体管辐射（8727KB）||学位论文||开放获取||CC BY-NC-SA||View Application Full Text|
|Recommend this item|
|Export to Endnote|
|Similar articles in Google Scholar|
|Similar articles in Baidu academic|
|Similar articles in Bing Scholar|
Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.