Method for selective removal of a material from a wafer's alignm

Details Method for selective removal of a material from a wafer's alignm Method for selective removal of a material from a wafer's alignm

1993-03-29

1993-12-21

Powell, William

Adhesive bonding and miscellaneous chemical manufacture

Delaminating processes adapted for specified product

Delaminating in preparation for post processing recycling step

156646, 156656, 156345, B44C 122, C23F 100, C03C 1500

Patent

active

052717984

ABSTRACT:
The present invention remedies the problems associated with selective etching of material, and in particular tungsten, by locally removing the material (e.g. tungsten) from the alignment marks through wet etching without the need for any photo steps. Either before or after chemical mechanical polishing, the wafers are flatly aligned and a tungsten etching agent is introduced through an etchant dispensing apparatus onto the alignment marks. Since an alignment mark is normally a few hundred microns in size and there is a large unused silicon real estate around the alignment marks, the alignment constraints vis-a-vis etchant dispensing apparatus and wafer are not very critical and tungsten plugs in the live dice are easily protected from the wet etch. After the etch, the etching byproduct is removed by suction and the wafer is cleaned by being rinsed in distilled water.

REFERENCES:
patent: 4992135 (1991-02-01), Doan
patent: 5147499 (1992-09-01), Szwejkowski et al.
patent: 5223083 (1993-06-01), Cathey et al.
patent: 5234539 (1993-08-01), Schiltz et al.
"Dual Damascene: A ULSI Wiring Technology" Kaanta et al., pp. 144-152. Jun. 11-12, 1991 VMIC Conference.

Affiliated with

Also associated with

Rating

Method for selective removal of a material from a wafer's alignm does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method for selective removal of a material from a wafer's alignm, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for selective removal of a material from a wafer's alignm will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-306218