Author: Dennis Lang Company: Fairchild Semiconductor Date Published: 1/17/2006
Pan Pacific Symposium
Abstract: Wafer level chip scale packages have long played an important role in the semiconductor industry. Its success has led to the proliferation of WLCSP packages into new applications with differing thermal requirements. One of the new applications is power conversion and signal protection. These applications achieve power densities requiring careful use of the advantages of the thermal properties of the device. This paper will study the thermal properties of the printed wiring board wafer level chip scale package connection. This will include solders, both leadfree and leaded. Underfill will also be examined from the thermal performance standpoint. Poor solder joints will be simulated to determine the thermal effects of errors in the surface mount process, to help engineers when investigating problems with WLCSP. Infrared testing will be used to determine the performance of the various methods of WLCSP attachment.