场区加固工艺技术研究

Research on Process of Radiation Harden Field

通过对应用在空间辐射环境下的CMOS LSI电离辐射效应的分析，从中找出电路加固的思路和方法。在电离辐射效应中，CMOS LSI的SiO2中正电荷的累积和SiO2-Si界面态的改变引起的参数变化，会严重影响电路的性能和功能。SiO2中正电荷的累积与其厚度成正比。在CMOS电路中，起MOSFET隔离作用的场区SiO2层厚度最大，是加固的重点之一。主要介绍一种场区加固工艺技术。通过制造SiO2-Si3N4复合场介质层，减小了场氧化层的厚度并改变了SiO2-Si界面状态。在电离辐射效应试验中，使CMOS电路的漏电电流在辐照前后的变化量降低了1．2个量级，为进一步提高电路的抗辐射性能提供了一种可供选择的工艺加固方法。

By analyzing the ionization radiation effect of the CMOS LSI （large scale integrated circuit）,the technology and the thought of the hardened circuit were found. In the ionization radiation effect, circuit function was affected heavily by the change of the parameter which was caused by the positive charge accumulation in SiO2 and the change of SiO2-Si interface state. The positive charge accumulation in SiO2 was direct radio to the thickness. In COMS circuit, the field where the thickness is the highest, supplying the use of isolation, is the most important. This article main introduces the technology of radiation hardened field. Though producing the SiO2-Si3N4 compound insulation layer, the thickness of field oxide is miniaturized and the interface state is change. In the ionization radiation effect experiment, the change of leak current is decreased 1 - 2 quantity after radiation. The technology which is a selective method improves the performance of anti-radiation.