Browse Prior Art Database

Align Write Head Throat to Read Head Stripe by Plasma Etching Endpoint

IP.com Disclosure Number: IPCOM000123491D
Original Publication Date: 1998-Dec-01
Included in the Prior Art Database: 2005-Apr-04
Document File: 1 page(s) / 36K

Publishing Venue

IBM

Related People

Hsiao, R: AUTHOR

Abstract

For a magneto-resistive (MR) head to deliver the optimum performance, the read and write heads must be aligned precisely. The disclosed method aligns write heads to MR sensors by plasma etching the structure that defines the write head zero throat.

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Align Write Head Throat to Read Head Stripe by Plasma Etching Endpoint

   For a magneto-resistive (MR) head to deliver the
optimum performance, the read and write heads must be aligned
precisely.  The disclosed method aligns write heads to MR sensors by
plasma etching the structure that defines the write head zero throat.

   In the disclosed fabrication process, endpoint sites are
first made during the MR stripe definition steps.  The back edge of
each endpoint site is aligned precisely with the back edge of a MR
stripe by mask design.  After the back edges of the MR sensors and
the endpoint sites are defined, an endpoint material such as SiO sub2
or Si sub3 N sub4 is deposited and patterned using a self aligned
technique.  During subsequent processing the endpoint sites are
protected, until the zero-throat defining process step.  After this
step, wafers are plasma etched with CF4/O2 chemistry.  During this
plasma etch, the zero-throat defining structures move towards the
back edges of the MR stripes and the endpoint sites.  Once the tips
of the structure are aligned with the back edges of the endpoint
sites, the endpoint material is exposed and etched by plasma.  The
etching of the endpoint material will produce optical emissions from
reaction products such as CN and SiFx.  The optical emissions can be
detected by an optical emission spectrometer and used to determine
the endpoint of this alignment etch, and a precise alignment of the
read and write head is ach...