an electronic structure , and associated method of fabrication , for coupling a heat spreader above a chip to a chip carrier below the chip . initially provided is a substrate , a chip on a surface of the substrate and coupled to the substrate , and the heat spreader . then a fillet of at least one adhesive material is formed on the chip and around a periphery of the chip . additionally , the heat spreader is placed on a portion of the fillet and over a top surface of the chip . the fillet couples the heat spreader to the substrate . an outer surface of the fillet makes a contact angle of about 25 degrees with the surface of the substrate . the small contact angle not exceeding about 25 degrees prevents cracking of the substrate that would otherwise result from thermal cycling .