Stacked die applications are being driven by the trend of smaller, tighter and more powerful devices. Stacked die, also termed 3D packaging, present several wire bonding and die attach challenges.
Die stacking is the process of mounting multiple chips on top of each other within a single semiconductor package. It is also known as chip stacking. This packaging process saves precious space on a PCB and results in better performance since shorter routing of interconnections between circuits results in faster signal transmission.
Interconnecting stacked die can be a great challenge if wire bonding is used. The manipulation of loops is required: low loops, short loops, long loops, short loops and deep access methods must be creatively employed.