论文部分内容阅读
半导体硅是发展电子工业的重要材料,其中含有几十ppb的硼、碳、氮杂质,对硅电子元件的电性能就有不良的影响。本工作利用我所1.2米回旋加速器产生的氘子,同时测定硅中痕量的硼、碳、氮。核反应为~(10)B(d,n)~(11)C、~(11)B(d,2n)~(11)C、~(12)C(d,n)~(13)N和~(14)N(d,n)~(15)O。产生~(11)C、~(13)N、~(15)O三个核素,半衰期分别为20.3分钟、9.96分钟和2.03分钟。选用7MeV能量的氘作轰击粒子,在此能量下,干扰反应~(15)O(d,t)~(15)O、~(16)O(d,αn)~(13)N和~(16)O(d,dn)~(15)O被抑制。另外,~(14)N(d,αn)~(11)C和~(14)N(d,t)~(13)N在此能量下截面很小,可不必考虑其干扰。
Semiconductor silicon is an important material for the development of the electronics industry. It contains dozens of ppb of boron, carbon and nitrogen impurities that have an adverse effect on the electrical properties of silicon electronic components. This work uses the deuterium produced by our 1.2-meter cyclotron to simultaneously determine trace amounts of boron, carbon and nitrogen in silicon. The nuclear reactions are ~ (10) B (d, n) ~ (11) C, ~ 11 B (d, 2n) ~ (11) C, ~ (14) N (d, n) ~ (15) O. The three nuclides of ~ (11) C, ~ (13) N and ~ (15) O were produced with half lives of 20.3 minutes, 9.96 minutes and 2.03 minutes, respectively. Deuterium with 7MeV energy is selected as the bombardment particle. Under this energy, the interference reaction of ~ (15) O (d, t) ~ (15) O, ~ 16) O (d, dn) ~ (15) O is suppressed. In addition, the cross sections of ~ (14) N (d, αn) ~ (11) C and ~ (14) N (d, t) ~ (13) N are very small under this energy.