Title :
Selective CVD tungsten as an alternative to blanket tungsten for submicron plug applications on VLSI circuits
Author :
Bradbury, D.R. ; Turner, J.E. ; Nauka, K. ; Chiu, K.Y.
Author_Institution :
Hewlett-Packard Co., Palo Alto, CA, USA
Abstract :
The authors discuss the major reasons and solutions for selectivity loss during selective tungsten deposition. By applying these solutions to the selective process the nucleation count on the dielectric can be reduced to less than 1 nuclei/cm/sup 2/. In addition, a novel process has been developed in most photoresist is used as a sacrificial layer and an antinucleation layer is used to reduce the tungsten nucleation count on the surface of the dielectric to 0 nuclei/cm/sup 2/. The chemistry involved in producing a low-resistance contact on 0.7- mu m-diameter contacts is also discussed. Electrical test results showing contact resistance data on 0.7- mu m-diameter via chains with corresponding bridging data are presented.<>
Keywords :
VLSI; chemical vapour deposition; metallisation; tungsten; 0.7 micron; VLSI circuits; W deposition; antinucleation layer; bridging data; contact resistance; low-resistance contact; nucleation count; photoresist sacrificial layer; selective CVD; selective deposition; selectivity loss; submicron plug applications; via chains; Contact resistance; Dielectric losses; Plasma applications; Plasma materials processing; Plugs; Resists; Surface contamination; Surface resistance; Tungsten; Very large scale integration;
Conference_Titel :
Electron Devices Meeting, 1991. IEDM '91. Technical Digest., International
Conference_Location :
Washington, DC, USA
Print_ISBN :
0-7803-0243-5
DOI :
10.1109/IEDM.1991.235450
