Title :
Thermally robust TiSi/sub 2/ on heavily doped polycrystalline silicon over severe topography
Author :
Perera, A.H. ; Lage, C. ; Sitaram, A.R. ; Woo, M.P. ; Tatti, S.
Author_Institution :
Adv. Products Res. & Dev. Lab., Motorola Inc., Austin, TX, USA
Abstract :
Using TiSi/sub 2/ to strap polysilicon over severe topography is hampered by the non-conformality of sputter deposited titanium (Ti) films. Thinning of the Ti translates into regions with thin silicide which degrade drastically when subject to 900 degrees C anneals. Etching back a thick polysilicon film to the desired thickness planarizes the surface for Ti deposition and eliminates the influence of underlying topography. The fabrication process outlined provides a final TiSi/sub 2/ sheet resistance approximately 2 Omega / Square Operator , after a 900 degrees C anneal in O/sub 2/.<>
Keywords :
annealing; etching; heavily doped semiconductors; integrated circuit technology; metallisation; silicon; sputter deposition; sputtered coatings; surface topography; titanium compounds; 900 C; O/sub 2/; Si; Ti; Ti deposition; TiSi/sub 2/-Si; anneal; fabrication process; heavily doped polycrystalline Si; severe topography; thermally robust TiSi/sub 2/; Annealing; Etching; Integrated circuit fabrication; Metallization; Silicon; Sputtering; Titanium compounds;
Conference_Titel :
Electron Devices Meeting, 1992. IEDM '92. Technical Digest., International
Conference_Location :
San Francisco, CA, USA
Print_ISBN :
0-7803-0817-4
DOI :
10.1109/IEDM.1992.307486
