Witte manufactures vacuum chucks for checking wafers

Electronic devices are getting smaller and smaller, whilst their functions become more extensive. This creates high demands on manufacturing technology in the semiconductor industry, which carries on the trend through complex thinning techniques. However, for extremely thinned down wafers special handling technology is required to avoid damages or breakage.
For several years Witte Bleckede, manufacturer of various vacuum clamping systems, has developed concepts, designed and manufactured so-called „wafer chucks “for the semiconductor industry. Damage-free wafer positioning on vacuum chucks is the positive result. The clamping surface consists of a micro-porous material (also suitable for clean room class 10); the microstructure allows very thin materials to be fixed absolutely flat and damage-free. Evenness and plan parallelism of <5µm is achievable. Removable stop pins simplify positioning of wafers in the correct clamping area. With this system, contrary to many other vacuum systems, it is not necessary to cover unused areas.
After checking the wafers are gently raised using lifting pins, operated with compressed air and with integrated stop action, and are removed using an end-deffector.