Thermal Conductivity of Therm-A-Gap™ Gel 30

Heat sinks are prevalent in electronics industry to remove heat from heat generating devices such as microprocessors and integrated circuits.  However, achieving perfect contact between the surfaces of these devices is challenging due to microscopic surface roughness and non-planarity between contact surface, resulting in air pockets between them that hinder effective heat transfer. Thermal Interface Materials (TIMs) are applied between the interfaces of two such components to enhance thermal coupling between them and provide effective heat conduction path. Parker Chomerics Therm-A-Gap^TM Gel 30, is a single component TIM that require no curing and can be dispensed over a range of heat generating components for effective cooling.  

Understanding Therm-A-GapTM Gel 30^TM

Therm-A-Gap^TM Gel 30 is extensively utilized in a wide range of interfacial contact applications across microprocessor, automotive, and semiconductor industries. It is known for its optimal flow rate, high thermal conductivity, and high temperature stability. Therm-A-Gap^TM Gel 30 is commonly used in automotive and electronic applications as high-performance gap filler. In this application sheet, we will investigate the thermophysical properties of Therm-A-Gap^TM Gel 30.

Equipment and Materials

The thermal conductivity (W/m·K), thermal diffusivity (mm²/s), and volumetric specific heat (MJ/m³K) of Therm-A-Gap^TM Gel 30 paste are measured using the Measurement Platform Versatile (MP-V) equipped with  Modified Transient Plane Source (MTPS) sensor and a custom-designed paste cell. The MP-V is specifically designed to test the absolute thermal conductivity, thermal diffusivity, specific heat and thermal effusivity of solids, liquids, pastes and powders. The MP-V features the powerful combination of the transient plane source (TPS, ISO 22007-2) and the transient hot-wire (THW, ASTM D7896-19) methods, providing a wide range of sensor options compatible with isotropic, anisotropic, and slab materials.

The Unique Properties of Therm-A-Gap™ Gel 30

Therm-A-Gap^TM Gel 30 is a fully cured, easily dispensable single-component TIM designed to simplify TIMS application by eliminating the need for multiple pad parts. At room temperature, Therm-A-Gap^TM Gel 30 is a pink paste with a density of 3.2 g/cc and flow rate of 20g/min. Its capacity to provide exceptional long-term thermal stability and performance are some of its primary characteristics, making it highly suitable for applications in memory and power modules, microprocessors, flat panel displays and automotive electronic control units. Gel 30 offers low thermal impedance for gaps of varying thicknesses, making it suitable for a wide range of bond line thicknesses and multiple device applications.

Measurement Platform Versatile (MP-V)

The MP-V is designed to test the absolute thermal conductivity, thermal diffusivity, specific heat and thermal effusivity of solids, liquids, pastes and powders. The MP-V features the powerful combination of the transient plane source (TPS, ISO 22007-2) and transient hot-wire (THW, ASTM D7896-19) methods with the variety of sensors that are compatible with it.  

Figure 1. Measurement Platform Versatile (MP-V)

A Closer Look at Transient Methods

Transient methods share similar theory with differences that are specific to their primary design. The sensors are electrically connected to a power supply and sensing circuit. A current passes through the sensors and creates an increase in temperature, which is recorded over time. The heat generated is then diffused into the sample at a rate dependent on the thermal transport characteristics of the material.

The Power of Intelligent Transient Plane Source (iTPS)

The MP-V features the proprietary intelligent Transient Plane Source (iTPS) function that is designed for automation of testing and analysis. iTPS requires only the sample name and dimensions as user input and the appropriate sensor and test parameters for each individual sample are determined.

The MTPS Sensor: Enabling Precise Measurements

The Modified Transient Plane Source Sensor (MTPS) is comprised of a TPS sensor configured with known backing insulation, permanently housed in a rugged single-sided configuration. This unique design combines intelligent design of sensor and measurement capabilities to generate bulk and directional properties for all materials. This sensor is capable of testing isotropic, anisotropic, slab and one-dimensional samples.

Figure 2. MTPS sensor and paste cell sample setup.

Unveiling the Thermal Conductivity of Therm-A-Gap™ Gel 30

Therm-A-Gap^TM Gel 30 was measured in the asymmetric configuration using absolute MTPS sensor and paste cell. Optimal measurement parameters of 3s and 110mW were determined using the proprietary iTransient Plane Source (iTPS) application to achieve appropriate temperature rise and accurate, repeatable results. Using the extended sensor correction, the contact resistance between the sensor and sample was measured and automatically removed. This ensures the best analysis possible is used for calculation.  

Table 1. Thermophysical measurements of Therm-A-Gap^TM Gel 30.

Therm-A-Gap^TM Gel 30, iTPS Parameters: 3 sec. 110 mW, 23°C, n=5.

Conclusion

The excellent thermal stability and high thermal conductivity of Therm-A-Gap^TM Gel 30 make it ideal for many different applications. In this application sheet, we investigated the thermal properties of Therm-A-Gap^TM Gel 30 and found that it was highly conductive with a thermal conductivity of 3.408 W/m·K.

Don’t miss out on this exclusive offer! Purchase an MP-V now and get 5 TPS modules included with your order. Upgrade your thermal conductivity testing capabilities.

References

[1] K.M. Razeeb, E. Dalton, G.L.W. Cross, A.J. Robinson, Present and future thermal interface materials for electronic devices, International Materials Reviews. 63 (2018) 1–21. https://doi.org/10.1080/09506608.2017.1296605.

[2] Therm-A-GapTM Gel 30 Data Sheet https://www.parker.com/Literature/Chomerics/Parker%20ChomericsGel-8010-Gel30.pdf