Heat Sink Based Micro Cooling

Rev. G&I.

0 Elsevier,

Therm.

Paris

(1998)

37, 781-787

Micro cooling systems for high density packaging*

Bernd Gromoll

Siemens

AC, Corporate

Technology,

Erlangen

Abstract-Future

3D electronics

packaging

systems

will require

micro

cooling

systems

that can be integrated

and permit

the

continued

use of air as a coolant.

To achieve

this, new types of silicon

micro

heat exchangers

were made using an anisotropic

etching

process.

Various

heat exchanger

configurations

and sizes were made using sandwich

and stacking

techniques.

They can

be used either as a heat exchanger

for direct cooling

with compressed

air or as a heat pipe and thermosyphon

for indirect

cooling

with fan-blown

air. The performance

characteristics

of the various

cooling

systems

are stated.

The micro-heat-pipe

can be used

for power

loss densities

of up to 3 Wcm-‘,

the direct

air cooling

up to 15 Wcm-’

and the thermosyphon

up to 25 Wcm-‘.

Cooling

performances

are achieved

that are otherwise

only possible

with liquid cooling.

The practical

application

of the micro

cooling

system

is demonstrated

using the example

of the Pentium

processor.

With a power

loss of 15 W. the high-performance

micro cooling

system

is able to limit the increase

in operating

temperature

to 15 K. The volume

of the micro heat exchanger

is

2.5 cm3 and therefore

considerably

smaller

than that of standard

heat sinks. 0 Elsevier, Paris

turbulence/

turbulence/

mass

mass

transfer

transfer

/ gas-liquid

model

interface

/ numerical

simulation

/ large

eddy

simulation

/ Navier-Stokes

equation

/ sheared

Resume

- Les futurs

systemes

de packaging

Clectroniques

3D exigeront

des micro-systemes

de refroidissement

aptes

a

I’integration

et permettant

de continuer

d’utiliser

l’air comme

agent

de refroidissement.

Pour satisfaire

a ce besoin,

on a

fabrique

de nouveaux

types de...