Method for preventing fluorine outgassing-induced interlevel die

Semiconductor device manufacturing: process – Making field effect device having pair of active regions... – Having insulated gate

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

438552, H01L 218238

Patent

active

057535485

ABSTRACT:
A method is described for forming P-channel field effect transistors having shallow source/drain junctions and improved reliability for CMOS circuits. The method involves forming both N-channel and P-channel FETs by alternate photoresist masking and ion implantation. The shallow junction self-aligned source/drain areas for P-channel FETs are formed by implanting boron difluoride (BF.sub.2) ions. In more conventional processing, the BF.sub.2 ions implanted in the P-channel FET gate electrodes during the source/drain implant results in outgassing of fluorine from the gate electrodes after the interlevel dielectric (ILD) layer is deposited. This can result in void formation, or delamination, at the interface between the gate electrode and the ILD. The current invention provides an improved process which uses a photoresist block-out mask to eliminate the implantation of the BF.sub.2.sup.+ ions in the P-channel FET gate electrodes during the formation of the self-aligned P.sup.+ source/drain regions. This prevents voids from forming at the gate electrode/ILD interface after the ILD layer is deposited and subsequent high-temperature processing steps are performed. The invention also reduces the enhanced boron diffusion in the P-FET gate oxide that can degrade the threshold voltage.

REFERENCES:
patent: 5405791 (1995-04-01), Ahmad et al.
patent: 5439834 (1995-08-01), Chen
S. Wolf, "Silicon Processing In The VLSI ERA vol. 2" Lattice Press, Sunset Beach, CA, p. 398, (1990).

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Method for preventing fluorine outgassing-induced interlevel die 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 preventing fluorine outgassing-induced interlevel die, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for preventing fluorine outgassing-induced interlevel die will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-1852602

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.