Title :
Reactive ion etching of thick CVD tungsten films
Author :
Jucha, Barry ; Davis, Cecil
Author_Institution :
Texas Instrum. Inc., Dallas, TX, USA
Abstract :
A manufacturable two-step etch process has been developed for VLSI/ULSI applications. SF/sub 6/, HBr, and CH/sub 3/Br are used in a high-power RIE mode to etch the bulk of the CVD tungsten. A low-power RIE plasma coupled with a remote microwave plasma is used to etch the remaining CVD tungsten film. The etch chemistry for the second step is SF/sub 6/, HBr, and CCl/sub 4/. The endpoint is detected optically during this second step. Ratios of HBr to various carbon passivants are examined for optimal etch conditions.<>
Keywords :
CVD coatings; VLSI; metallic thin films; metallisation; sputter etching; tungsten; HBr; SF/sub 6/; SF/sub 6/-HBr; VLSI/ULSI; W; bromomethane; etch chemistry; high-power RIE mode; low-power RIE plasma; optical endpoint detection; optimal etch conditions; remote microwave plasma; tetrachloromethane; thick CVD films; two-step etch process; Etching; Manufacturing processes; Optical detectors; Optical films; Plasma applications; Plasma chemistry; Plasma materials processing; Tungsten; Ultra large scale integration; Very large scale integration;
Conference_Titel :
VLSI Multilevel Interconnection Conference, 1988. Proceedings., Fifth International IEEE
Conference_Location :
Santa Clara, CA, USA
DOI :
10.1109/VMIC.1988.14189
