Semiconductor wafers. Technician manipulating a semiconductor wafer in a quality control laboratory. Integrated circuits are in the background. Wafers are divided up into blocks to make the integrated circuits ('chips') used in electronic devices. Integrated circuits are made by impregnating the wafer with impurities to create transistors. Tens of thousands of transistors can be fitted on a single chip and connected by conducting pathways. The technician is wearing gloves to protect the chips. Exposed chips are extremely vulnerable to contamination such as human hairs and flakes of skin.