Browse Prior Art Database

TCM Thermal Reticle

IP.com Disclosure Number: IPCOM000119765D
Original Publication Date: 1991-Feb-01
Included in the Prior Art Database: 2005-Apr-02
Document File: 1 page(s) / 46K

Publishing Venue

IBM

Related People

Abrami, AJ: AUTHOR [+6]

Abstract

The cooling of multichip modules has the problem of temperature range from chip to chip due to varying individual powers on the substrate. Disclosed is a new method by which temperature of low power chips is increased. The temperature increase is accomplished by disposing a thin layer of organic polymer film between the chip and a heatsink or a TCM piston. The figure illustrates two embodiments; the first having the film affixed to the chip and the second having the film material affixed to the heatsink. Having the film interposed between the chip and the heatsink increases the thermal resistance to heat flow at that site, thus, increasing the chip temperature. The amount by which the chip temperature is raised is proportional to the thickness of the film.

This text was extracted from an ASCII text file.
This is the abbreviated version, containing approximately 97% of the total text.

TCM Thermal Reticle

      The cooling of multichip modules has the problem of temperature
range from chip to chip due to varying individual powers on the
substrate.  Disclosed is a new method by which temperature of low
power chips is increased. The temperature increase is accomplished by
disposing a thin layer of organic polymer film between the chip and a
heatsink or a TCM piston.  The figure illustrates two embodiments;
the first having the film affixed to the chip and the second having
the film material affixed to the heatsink.  Having the film
interposed between the chip and the heatsink increases the thermal
resistance to heat flow at that site, thus, increasing the chip
temperature.  The amount by which the chip temperature is raised is
proportional to the thickness of the film.  The thickness required
for each chip is determined by thermal modelling, and is a function
of the chip power, and the chip's position in the cooling package.
By this method the range of chip junction temperatures is greatly
reduced, which can be an advantage in product and burn-in
applications.

      In a third embodiment (not illustrated) a thermal reticle,
having a checkerboard pattern is disposed between the pistons (or
other heat sink devices) and the chips. Each square in the
checkerboard corresponds to a chip location and is independently
treated with as much of the film as is required to achieve the
desired thermal resistance between a given chip and the corresponding
pi...