Browse Prior Art Database

Bumped Quartz Chip Processing

IP.com Disclosure Number: IPCOM000119022D
Original Publication Date: 1997-Oct-01
Included in the Prior Art Database: 2005-Apr-01
Document File: 2 page(s) / 45K

Publishing Venue

IBM

Related People

Deseez, C: AUTHOR [+2]

Abstract

The purpose is to make chips using Controlled Collapse Chip Connection (C4) bumps made of quartz, which are needed to control the chip assembly process (chip alignment, C4 coating, etc.). To improve the C4 process modeling, some features should be added on the quartz wafer before the bumping process (like a polyimid layer) or patterns (like dice alignment marks). The C4 bumps are deposited on the wafer made of quartz as they are deposited with the standard bumping process.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 86% of the total text.

Bumped Quartz Chip Processing

      The purpose is to make chips using Controlled Collapse Chip
Connection (C4) bumps made of quartz, which are needed to control the
chip assembly process (chip alignment, C4 coating, etc.).  To improve
the C4 process modeling, some features should be added on the quartz
wafer before the bumping process (like a polyimid layer) or patterns
(like dice alignment marks).  The C4 bumps are deposited on the wafer
made of quartz as they are deposited with the standard bumping
process.

      The main difficulty is to dice the quartz wafer without
breaking the wafer and the dicing saw, while the right chip size is
obtained.

      For this purpose, using a dicer tool, which is normally
employed for quartz cutting to make parts like quartz boats for the
chip manufacturing, is suggested.  This tool is not adapted to the
silicon chip dicing.  A Maeger & Burger type "TS 33" dicer is
adequate in all respects to perform the dicing operation.  After C4
bumping, the wafer  is glued on an aluminum chuck with a mix of wax
and paraffin, and the assembly is heated.  The dicing is then made
with a saw, which has a thickness of 1mm.  To have a good chip size
dicing, the alignment of the  saw is not in the center of the chip
kerf but is slightly skewed, as shown in the Figure.  During the
dicing operation, the dicer tool is cooled with a jet of water
solvent oil.  After dicing, the chips are unstuck by heating in
toluen.

      With this...