Control of Point Defects in Si and its Application to Process Simulation

在直接覆盖氮化硅(Si3N4)薄膜的硅结构中，研究了Si3N4薄膜和衬底在退火过程中的应力及其对B(B)扩散和扩展缺陷的影响。在退火过程中，Si3N4薄膜产生拉应力，在衬底表面产生压应力。从Si_3N_4薄膜厚度和退火温度与B扩散系数和衬底应力的关系的结果来看，B的扩散是缓慢的，衬底在薄膜下的退火过程中具有高的弹性压缩应变。这些结果表明，过剩空位是由弹性压缩应变产生的，从而阻碍了B在间隙中的扩散。本文还研究了Si_3N_4薄膜对磷(P)和锑(Sb)在硅中扩散的影响。在氮化薄膜下，P的扩散被抑制，而Sb在Si中的扩散被促进。确定了P和Sb在Si中扩散的间隙组分分别约为0.96和0。

In the structure of silicon directly covered with silicon nitride (Si_3N_4) films, stresses of Si_3N_4 films and substrates during annealing, and its effect on boron (B) diffusion and extended defects are studied. During annealing, tensile stress is generated in the Si_3N_4 film, resulting in compressive stress at the surface of the substrates. From the results of Si_3N_4 film thickness and annealing temperature dependence on both B diffusivity and stress in the substrates, B diffusion is found to be retarded and the substrates are found to have high elastic compressive strain during annealing under the films. These results indicate that excess vacancies are generated by elastic compressive strain, causing the retardation of interstitial-mediated diffusion of B.The effect of Si_3N_4 films on diffusion of phosphorus (P) and antimony (Sb) in Si has also been studied. P diffusion is retarded, while Sb diffusion is enhanced in Si under nitride films. It is determined that fraction of interstitialcy component in P and Sb diffusion in Si is approximately 0.96 and 0, respectively.