Agere Systems Inc.

Agere Systems Guardian Corp.

Lucent Technologies Inc.

Thomas Craig Esry

Daniel Charles Kerr

Simon John Molloy

Nace Layadi

Mario V Pita

Sylvia Marci Luque

Oliver Desmond Patterson

Edward Paul Martin, Jr

Bradley J Albers

Paul Edward Wheeler

Mario Pita

David Huibregtse

Milton Beachy

Thomas M Oberdick

Donald Stephen Bitting

A method of preventing formation of stringers adjacent a side of a CMOS gate stack during the deposition of mask and poly layers for the formation of a base and emitter of a bi-polar device on a CMOS integrated circuit wafer. The stringers are formed by incomplete removal of a hard mask layer over an emitter poly layer over a nitride mask layer. The method includes overetching the hard mask layer with a first etchant having a higher selectivity for the emitter poly material than for the material of the hard mask, determining an end point for the overetching step by detection of nitride in the etchant and applying a poly etchant that is selective with respect to nitride to remove any residual emitter poly.

Stringer elimination in a BiCMOS process

A method and apparatus for identifying crystal defects in emitter-base junctions of NPN bipolar transistors uses a test structure having an NP junction that can be inspected using passive voltage contrast. The test structure eliminates the collector of the transistor and simulates only the emitter and base. Eliminating the collector removes an NP junction between collector and substrate of a wafer allowing charge to flow from the substrate to emitter if the emitter-base junction is defective since only one NP junction exists in the test structure. In one embodiment, the test structures are located between dies on a wafer and may be formed in groups of several thousand.

Test structure and method for yield improvement of double poly bipolar device

A patterned film structure within a semiconductor device includes a pattern formed within a hardmask film, and a pattern formed within an underlying semiconductor or metal film beneath the hardmask film. The etch bias of both isolated and nested features formed within the patterned structure, is substantially the same with respect to a masking film formed over the hardmask film.

Semiconductor device having reduced line width variations between tightly spaced and isolated features

A process for forming a patterned film structure within a semiconductor device. The process sequentially forms a pattern within a hardmask film and than within a semiconductor or other film formed beneath the hardmask film. The etch bias of both isolated and nested features formed within the films, is substantially the same with respect to a masking film formed over the hardmask film. The process includes a hardmask film etching sequence including an argon treatment step and a hardmask film etching step which is resistant to localized etching effects and includes O and C F as etchant gasses.

Process for improving line width variations between tightly spaced and isolated features in integrated circuits

The quartz shadow ring of a conventional plasma etching apparatus is desirably coated with material which inhibits the liberation of oxygen into the plasma. Investigation has shown that the liberated oxygen degrades etching uniformity across the wafer.

Integrated circuit fabrication

Growing community of inventors

Orlando, FL, United States of America

Thomas Craig Esry