Apparatus and method for preparing backside-ground wafers for testing

A method for preparing a backside-ground wafer for testing by using a wafer mounting block comprising the steps of:

• providing a wafer mounting block that comprises:
• a slanted block formed of a rigid material having a top surface with a slant angle from a horizontal plane between about 10° and about 30°, said top surface generally having a rectangular shape;
• a stopper of linear, elongated shape having a height of at least 5 mm fixedly positioned at and parallel to a bottom edge of said top surface of the slanted block;
• two guiding strips of linear, elongated shape having a height of at least 5 mm fixedly positioned spaced-apart and parallel to two sides of said top surface, said two guiding strips are spaced-apart by a distance that is at least a diameter of said calibration wafer;
• positioning a calibration wafer that has a pattern formed of an insulating material on a top side on said top surface of the slanted block in-between said stopper and said two guiding strips;
• applying at least three drops of water with each one sufficiently apart from the others on said top side of the calibration wafer;
• providing a backside-ground wafer having a ground backside and a front side to be tested;
• mating said ground backside of the backside-ground wafer to said top side of the calibration wafer intimately with said at least three drops of water therein between;
• and
• removing a calibration wafer/backside-ground wafer assembly that are bonded together from said wafer mounting block.