CN-1735 underfill is designed to enhance thermal cycle performance of IC packages with pitches as fine as 0.3mm. Reportedly enhances ruggedness for drop and bend test performance. Has a CTE of 40 ppm/°C. Reportedly can be reworked using elevated temperature (170°C to 180°C) to remove underfill fillet.
Zymet, www.zymet.com