A new gap filler material from Henkel has not only extreme stress tolerance and thermal management capabilities, but also protects electronic devices against electromagnetic interference (EMI). The company says this is the first time these features have been united in a single thermal interface material (TIM). This is important for engineers designing increasingly smaller electronic devices that host a wider range of frequencies used by multiple applications.
The new material is Gap Pad EMI 1.0, the latest in the family of Gap Pad gap filling thermal management products. The Gap Pad TIM family is one of several Henkel acquired when it purchased The Bergquist Company in September last year. The ability of these materials to deflect stress over time at low pressures, including compressive modulus (Young's Modulus) and compression/deflection data, is described in an application note you can download here.
In addition, Henkel's new version of Gap Pad integrates the ability to absorb electromagnetic energy, with thermal conductivity of 1.0 W/m-K and EMI absorption for frequencies above 1GHz. Its improved wet-out at the interface results in thermal performance superior to competitive materials that have a similar rating. The material's natural tack on one side also enhances its thermal conductivity, eliminating the need to add thermally impeding adhesive layers, as well as simplifying any required component rework.
Gap Pad EMI 1.0 is also highly soft and compliant. This is an advantage in gap filling material used for sensitive electronic components, since a high degree of flexibility lets the material conform to a variety of topographies. This minimizes pressure on PCBs, component leads and solder joints, and deflects stress from them, especially during assembly. Compared to traditional EMI materials with high modulus, the new material's lower modulus helps improve reliability by reducing field failures caused by solder joint stress and fractures.
Applications include power electronics, consumer, telecommunications, automotive and Wi-Fi/Bluetooth-enabled LEDs, said Doug Dixon, Henkel's global marketing director. Gap Pad EMI 1.0 comes in several thicknesses and custom part sizes in both sheet and die-cut formats.
Ann R. Thryft is senior technology editor, materials & assembly, for Design News. She's been writing about manufacturing- and electronics-related technologies for 27 years, covering manufacturing materials & processes, alternative energy, and robotics. In the past, she's also written about machine vision and all kinds of communications.