The production of chips consists of many individual steps, starting with the growth of a silicon cylinder, the ingots, continuing with the production of the wafers and the lithographic exposure of the integrated circuits, passing through several tests and ending with the encapsulation of the chips in packages
. Silicon rods or cylinders: The starting material for chip fabrication is a grown semiconductor cylinder made of silicon or another semiconductor materialdoped with various chemical elements such as boron (B), phosphorus (P), arsenic
(As) and antimony (Sb). Thediameters of the silicon cylinders are between 50 mm and 450 mm, their length between 50 cm and 1 m.
Wafers: The ingots are cut into extremely thin slices by laser technology. The thickness can be only a few hundred micrometers. The wafer surfaces are cleaned in several cleaning and polishing processes, freed from scratches and polished several times in the clean room. They then undergo a final cleaning and an exact inspection of the wafer surface. Before the wafer surface can be lithographically processed, a photoresist, the resist
, is applied to the surfaceLithographic processing: In lithographic processing, the masks for the chip structures are extremely reduced in size using lens systems and projected onto the wafer. UV light is used for this projection because it has shorter wavelengths than daylight and thus achieves a higher resolution. DUV lithography and EUV lithography
are used as projection methods with which the chip structures are burned into the resist. Subsequently, the structures burned into the photoresist are developed by etching and heatingDie preparation of the exposed chips: After the chip structures are exposed, the photoresist is removed. This completes a wafer processing cycle for a single chip layer. Once all required cycles are completed, the chip cores are cut out of the wafer by dicing and tested. Finally, the chips are encapsulated in a special package using packaging.