Thermal Resistance of Heat Sink Interface Material Testing Device (TIM Tester) Progress Report 3/8/2004

Re-Introduction Thermal interface materials (TIMs) fill gaps between electronic devices and heat sinks. TIMs are now being designed with very small thermal resistances. Current standard does not test modern TIMs with high certainty [1],[2].

Re-Introduction Team will design and build the structure, plumbing, and force application systems. Dr. Recktenwald and John Farley will design thermal data acquisition and data reduction systems.

Product Design Specifications Supports the Transient Method Test Several Types of TIMs Variable Pressure Removable Pucks High Repeatability

Final Design Progress Overall concept has been established Analysis of components and Assemblies has begun

Plumbing System Heater and Chiller with circulating loops

Plumbing System Progress Heater and Chiller are being researched Several possible valves have been identified Cross-Linked Polyethylene hose for the pipes Closed loop system including puck with cavity

Force Actuator Teflon Guide Rails Load Cell Aluminum Pucks

Alignment Rotational Center on Center Parallelism

Aluminum Pucks Wet Puck Dry Puck

Force Actuator Requirements Up to 250 lbs Up to 250 lbs Volts DC Volts DC 4-8 inches of stroke 4-8 inches of stroke Low backlash Low backlash Not self-locking Not self-locking Ball Screw Driven Ball Screw Driven

Force Actuator [3]

Load Cell Requirements 250 lbs 250 lbs Fits within puck guide rails Fits within puck guide rails As short as possible (column stability) As short as possible (column stability) Compression Only Compression Only

Candidate Load Cell Button type (load button) Compressive only 250 lb capacity Dimensions Diameter = 1.25 inches Diameter = 1.25 inches Height = 0.4 inches Height = 0.4 inches Easily mounted [4]

Force Actuator Teflon Guide Rails Load Cell Aluminum Pucks

References [1]Kearns, Don, “Improving Accuracy and Flexibility of ASTM D 5470 for High Performance Thermal Interface Materials,” 19th IEEE SEMI- THERM Symposium, pg , [2]Lasance, Clemens J.M., Electronics Cooling, vol. 9, no. 4, [3] 3/8/ [4] Load-Cell.cfm, 3/8/ Load-Cell.cfm