1). Field of the Invention
This invention relates to an apparatus that is used for full-wafer testing and/or burn-in testing and/or built-in self-testing.
2). Discussion of Related Art
Microelectronic circuits are usually fabricated in and on semiconductor wafers. Such a wafer is subsequently “singulated” or “diced” into individual dies. Such a die is typically mounted to a supporting substrate for purposes of providing rigidity thereto and electronic communication with an integrated or microelectronic circuit of the die. Final packaging may include encapsulation of the die and the resulting package can then be shipped to a customer.
It is required that the die or the package be tested before being shipped to a customer. Ideally, the die should be tested at an early stage for the purposes of identifying the defects that occur during early-stage manufacturing.
The earliest stage that a die can be tested is after completion of the manufacture of microelectronic circuits at wafer level and before a wafer is singulated. Full wafer testing carries with it a number of challenges. One challenge in full wafer testing is that there is a large amount of contacts on a wafer and that a large number of power, ground, and signal connections thus have to be made. Another challenge is that burn-in testing requires a thermal management system that can maintain the wafer stable at a relatively high temperature, while providing a system that is simple to operate and relatively inexpensive.