Semiconductor wafer. Multiple exposure image of a semiconductor wafer illuminated by bright light. Many tiny individual electronic circuits known as integrated circuits (ICs) can be seen. The wafer is a thin slice of silicon on which hundreds of the ICs are formed. They are made by adding impurities to the silicon or by laser etching. The wafer can then be sliced into individual ICs known as chips". Chips of various different functions can be combined on a square of silicon measuring 5 cm. This is how the microprocessors which make modern computers possible are made. The IC has greatly increased electrical equipment's capability and reliability."