Issue link: https://iconnect007.uberflip.com/i/1460418
MARCH 2022 I PCB007 MAGAZINE 21 product's use. e air gap filler has no woven glass reinforcement allowing it to more effec- tively fill completely the space between mating surfaces and it bonds effectively and securely with only slight mechanical contact pressure, adding to its ease of use. e low temperature bond creates a solid, long-lasting thermome- chanical connection between constituent ele- ments of the cooling chain for the power mod- ule during the assembly process. In addition, Aismalibar has developed other cost effective, self-adhering TIM variations comprised of the novel adhesive in combination with highly conductive copper foils coated with a thin electrically isolating layer (Isolcopper). ese inexpensive self-adhesive, thermally conduc- tive foils are available as cost-effective coat- ing options in the new TIM family of solutions which help simplify the thermal management. e current roster of thermal solutions is based on reinforced dielectric polymerized interface material designed for high dielec- tric isolation and low thermal resistance both in normal and a high Tg (180°C with reduced CTE) formulations. e products are funda- mentally a thin dielectric layer, high dielec- tric strength, high thermal conductivity, and low thermal resistance comprised of a glass fabric base, enriched with mineral fillers. e product has a thermal conductivity of 2.2 W/ mK with dielectric strengths greater than 4 KV (70 mm dielectric) or 6 KV (100 mm dielectric thickness) and a low thermal resistance R th of 0.315 (70 mm), or 0.45 Kcm 2 /W (100 mm), to efficiently dissipate the heat generated by the power components to the cooling elements. Importantly for many applications, the prod- uct is silicone free and can be easily adapted to pick and place automation. Again, a very important solution in the Ais- malibar stable of products is Isolcopper—a thin copper (35-80 micron) clad with an ultra- thin dielectric layer filled with high end min- eral content. e product combines the ben- efits of the excellent thermal conductivity of copper with a specially developed dielectric Figure 2: The novel "air gap filler" mitigates small voids or micro air pockets which are found at the interface between electronic components and the thermal spreading element dedicated to heat removal, especially when using thermal pastes which are difficult to spread evenly. Because air is a poor conductor of heat, void elimination is necessary to prevent hot spots which can result in thermal damage to components and system failures.