Browse Prior Art Database

Depotting Technique for Plastic Devices

IP.com Disclosure Number: IPCOM000111333D
Original Publication Date: 1994-Feb-01
Included in the Prior Art Database: 2005-Mar-26
Document File: 2 page(s) / 20K

Publishing Venue

IBM

Related People

Pakes, K: AUTHOR [+2]

Abstract

A technique for selectively etching away plastic encapsulant from a microelectronic device for failure analysis is disclosed. Encapsulant can be removed from the selected area with minimal damage to the rest of the device.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 100% of the total text.

Depotting Technique for Plastic Devices

      A technique for selectively etching away plastic encapsulant
from a microelectronic device for failure analysis is disclosed.
Encapsulant can be removed from the selected area with minimal damage
to the rest of the device.

      First, mask off the area to be removed with masking tape.  Then
coat the whole device in a noble metal such as gold or platinum,
using vapor deposition.  Remove the mask and etch the encapsulant
away to the desired depth, using drops of hot fuming nitric acid on
the uncoated area.  Rinse periodically with deionized water to remove
debris.  The noble metal protects the body of the device, minimizing
damage to coated areas.