Peroxide clean before buried contact polysilicon deposition

Details Peroxide clean before buried contact polysilicon deposition Peroxide clean before buried contact polysilicon deposition

1993-05-07

1994-07-12

Thomas, Tom

Fishing, trapping, and vermin destroying

437228, 437238, 148DIG17, 148DIG118, H01L 2144

Patent

active

053288670

ABSTRACT:
A method of removing impurities from the surface of an integrated circuit and forming a uniform thin native oxide layer on the same surface of an integrated circuit is described. A hydrofluoric acid solution, followed by a rinse and spin dry, is often used to remove gate oxide from within an opening etched in a polysilicon layer. The rinsing leaves water spots. Spin drying leaves impurities where water tracks were. An H.sub.2 O.sub.2 cleaning is performed to remove the water spots. After the cleaning, a uniform thin layer of native oxide is formed on the surface of the silicon substrate. A second layer of polysilicon is deposited over this first thin native oxide layer and doped with an implant dosage chosen so that it will go through the uniform native oxide layer. The substrate is annealed to drive in the buried contact. Processing continues to form polysilicon or silicide gate electrodes. Source and drain regions are formed within the openings to the silicon substrate between the gate electrodes. Spacers are formed on the sidewalls of the gate electrodes. An insulating layer is deposited over the surface of the silicon substrate. Contact openings are etched through the insulating layer to the second polysilicon layer and to the silicon substrate. A metal layer is deposited over the insulating layer and filling the openings to the second polysilicon layer and the silicon substrate. The metal layer is patterned, completing the formation of the buried contacts within the integrated circuit.

REFERENCES:
patent: 4863561 (1989-09-01), Freeman et al.
patent: 5147499 (1992-09-01), Szwejkowski et al.
Translation of Ito 2-307277.

Affiliated with

Also associated with

Rating

Peroxide clean before buried contact polysilicon deposition does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Peroxide clean before buried contact polysilicon deposition, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Peroxide clean before buried contact polysilicon deposition will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-396248