Determination and optimization of film adhesive cure in board-on-chip packaged semiconductors

Summary form only given. Adequate die-to-substrate adhesion is essential to ensure board-on-chip (BOC) package integrity during and after the manufacturing process. Inadequate adhesion can result in a variety of defects, such as die adhesion failure, marginal wire bond, broken wire and bent leads, and ultimately lead to electrical failure. The BOC die attach method of laminations using film adhesives provides ease of application and consistent bond line thickness. Processing problems due to inconsistency of film adhesive manufacture, however, can occur. Differential scanning calorimetry (DSC), contact angle, and hardness were used to determine the consistency of blended-polymer b-staged thermosets. These analytical techniques were shown to be useful incoming inspection monitors or preapplied film adhesives and provided a means of eliminating inadequate adhesion at die attach.