Title :
Effect of H/sub 2/O partial pressure and temperature during Ti sputtering on texture and electromigration in AlSiCu-Ti-TiN-Ti metallization
Author :
Yoshida, Takafumi ; Hashimoto, Shuji ; Mitsushima, Y. ; Ohwaki, T. ; Taga, Y.
Author_Institution :
Toyota Central Res. & Dev. Labs. Inc., Aichi, Japan
fDate :
March 31 1998-April 2 1998
Abstract :
The effect of residual gas constituents and substrate temperature during Ti sputtering on the texture of TiN/Ti films deposited on SiO/sub 2//Si substrates has been investigated. The Ti(002) and TiN(111) preferred texture of the films deposited at 350°C was improved drastically by increasing the H/sub 2/O partial pressure from lxl0-9 to 3xi0-8 Torr. Both the Ti(002) and TiN(lll) texture showed a similar H/sub 2/O partial pressure and substrate temperature dependence because of the epitaxial transfer between these planes. The improved Ti(002) texture was attributed to the self-assembly of Ti atoms on the SiO/sub 2/ surface, which had a low surface free energy due to the formation of surface OH groups. The AlSiCu/Ti/TiN/Ti film fabricated with the highly-textured TiN/Ti film showed a strong Al(111) texture and had a smooth surface. Moreover, interconnects from this improved film had longer EM lifetimes.
Keywords :
aluminium alloys; copper alloys; electromigration; integrated circuit interconnections; integrated circuit metallisation; integrated circuit reliability; integrated circuit testing; silicon alloys; sputter deposition; surface texture; titanium; titanium compounds; water; 0.000001 to 0.00003 mtorr; 350 C; Al(111) texture; AlSiCu-Ti-TiN-Ti film; AlSiCu-Ti-TiN-Ti metallization; AlSiCu-Ti-TiN-Ti-SiO/sub 2/-Si; H/sub 2/O; H/sub 2/O partial pressure; H/sub 2/O partial pressure effects; SiO/sub 2/-Si; Ti atom self-assembly; Ti sputtering; TiN(111) preferred texture; TiN-Ti film texture; electromigration; epitaxial transfer; interconnect EM lifetimes; interconnects; residual gas constituents; smooth surface; substrate temperature; surface OH group formation; surface free energy; surface texture; temperature effects; textured TiN-Ti layer; Films; Gases; Resistance; Silicon; Substrates; Surface treatment; Tin;
Conference_Titel :
Reliability Physics Symposium Proceedings, 1998. 36th Annual. 1998 IEEE International
Conference_Location :
Reno, NV, USA
Print_ISBN :
0-7803-4400-6
DOI :
10.1109/RELPHY.1998.670666
