Based in Livermore, CA, FormFactor, Inc. (FORM) is an original equipment manufacturer (OEM) of automated wafer probe cards that are used in the back-end portion of the semiconductor integrated circuits (ICs) manufacturing process. Wafer probe card sales accounted for 99% of fiscal 2004 revenue. FORM derives the remainder of its revenue from product sales, licensing, development fees and royalties. The company went public in an IPO during June 2003.
The back-end of the manufacturing process takes place after a wafer (usually made of silicon) has completed the device formation stage, in which multiple copies of an IC device have been constructed on it. A wafer prober then moves the wafer so that each IC device's electrical contact points are properly aligned with the probe card's pins, facilitating the parametric or functional testing of the device. Parametric testing is done both during and at the completion of the device fabrication process. Functional testing, completed after final construction, determines whether the device meets performance specifications (wafer sorting). Following the wafer sort, the wafer is cut or separated into individual die. Electrical leads are then attached to the die surface. This is followed by die encapsulation and packaging within an environmentally protective encasement. The purpose of the die package or encasement is to protect the semiconductor device from environmental elements and secure the electrical contacts to the protruding electrical leads. In addition, the encasement acts as a medium through which thermal energy or heat is dissipated from the die. A final test is then conducted on the chip. Wafer probers are used in wafer sorting applications roughly 85% of the time, while the rest are used in parametric testing. Thus most of the testing is done in the back-end of the fabrication process. Each probe card is custom-built for each specific wafer, as well as for the test equipment that accepts the probe card's electronic information. Functionally, this test equipment increases the efficiency of the manufacturing process through the detection and removal of defective semiconductor devices prior to final assembly. The primary challenges facing wafer prober and probe card manufacturers are the transition to larger wafers, the shrinking of device sizes, increasing throughput requirements, and devices running at greater speeds and at lower power.(Read more at Wikinvest )