Epitaxial Growth of CoSi2 Layer on (100)Si Substrate using CoNx Interlayer deposited by Reactive Sputtering

A novel method was proposed to grow an epitaxial $CoSi_2$ on (100)Si substrate. A $CoN_x$ interlayer was deposited by reactive sputtering of Co in an Ar+$N_2$ flow. From the Ti/Co/$CoN_x$/Si structure, a uniform and thin $CoSi_2$ layer was epitaxially grown on (100)Si by annealing above $700^{\circ}C$. Two amorphous layers were found at the $CoN_x$/Si interface, where the top layer has a silicon nitride (Si-N) bonding state with some Co content and the bottom layer has a Co-Si intermixing state. The SiNx amorphous layer seems to play a critical role of suppressing the diffusion of Co into Si substrate for the direct formation of epitaxial $CoSi_2$.

반응성 스퍼터링법으로 증착된 CoNx 중간층을 이용한 (100)Si 기판 위에서의 에피택셜 CoSi2 성장 연구