Control of solid-phase reaction dynamics and carbon engineering for nanofabrication of group-IV

在这个项目中，我们研究了C的加入对薄膜生长和非均质材料之间界面反应的控制，以发展未来Si ULSI器件的纳米制造。结果表明：(1)研究了C离子注入对NiSi/Si（001）触点结晶性能和电学性能的影响。大于3×10^<14> cm^<-2>的C注入量能有效抑制NiSi层的团聚，即使在750℃退火后也能防止NiSi层的片阻增加。(2)注入剂量为3×10^<15> cm^<-2>的C离子可降低NiSi/p^+-Si界面的接触电阻。C的掺入抑制了ni形成过程中B原子在界面处的再分布，增强了B原子向界面的堆积。因此，添加C的样品界面处载流子浓度高于未添加C的样品，从而导致接触电阻降低。(3)通过STM观察，研究了C对Si（100）衬底外延NiSi_2层初始生长的影响。C的加入有效抑制了NiSi_2/Si外延界面{111}晶面的形成，促进了NiSi_2外延岛各畴的各向同性生长。结果表明，随着C原子沉积量的增加，NiSi_2外延层的平整度和覆盖度均有所提高。(4)用STM观察了在Si（001）衬底上共沉积和Ge、C交替沉积Ge_<1-x>C_x层的初始生长。表面合理分布的Si-C键有效抑制了C簇的形成和Ge三维岛的生长，使Ge_<1-x>C_x层均匀生长。

In this project, we investigated the control of the thin film growth and the interfacial reaction between heterogeneous materials by the incorporation of C in order to the development of the nanofabrication of future Si ULSI devices. The following results were obtained :(1) The effect of the C ion implantation on the crystalline and electrical properties of NiSi/Si(001) contacts has been investigated. The C implantation with a dose higher than 3×10^<14> cm^<-2> is effective to suppress the agglomeration of NiSi layers, and to prevent the increase in the sheet resistance of NiSi layers even after annealing at 750℃.(2) The contact resistance of the NiSi/p^+-Si interface can be reduced by the C ion implantation with a dose of 3×10^<15> cm^<-2>. The redistribution of B atoms at the interface during the NiSi formation is suppressed with the incorporation of C, and the pile-up of B toward the interface is enhanced. As a result, the carrier concentration at the interface in the sample with C is higher than that without C, which leads to the reduction of the contact resistance.(3) The effect of C on the initial growth of epitaxial NiSi_2 layers on Si(100) substrates has been investigated with the STM observation. The incorporation of C is effective to suppress the formation of {111} facets at the epitaxial NiSi_2/Si interface, and to enhance the isotropic growth of individual domains of epitaxial NiSi_2 islands. As a result, the flatness and the coverage of epitaxial NiSi_2 layers are improved with increasing the amount of deposited C atoms.(4) The initial growth of Ge_<1-x>C_x layers on Si(001) substrates with the codeposition and the alternate deposition of Ge and C has been investigated with the STM observation. The Si-C bonds properly distributed on the surface are effective to suppress the formation of C cluster and the growth of Ge 3D islands, which leads to the homogeneous growth of Ge_<1-x>C_x layers.