How does an integrated circuit combine electronic components on one chip?

An integrated circuit (IC) combines electronic components—such as transistors, diodes, resistors, and capacitors—onto a single, monolithic chip by fabricating them directly onto a thin substrate of semiconductor material, typically silicon.1

The process involves building up to 30 or more layers on a silicon wafer through a series of precise manufacturing steps:23

• Layering and Modification: The wafer is modified by depositing new material, etching away unwanted sections, or implanting impurities to alter the material's composition.2
• Doping: By introducing specific impurities like arsenic or boron, engineers create n-type (excess electrons) and p-type (positive holes) regions. These adjacent regions form the junctions necessary for transistors to conduct electricity.3
• Photolithography: To define the exact geometry of components, a light-sensitive "resist" is applied and exposed to light through a patterned mask. This allows for the selective etching or deposition of materials at microscopic scales.34
• Interconnection: Thin paths of metal, such as aluminum or copper, are deposited to act as wires, connecting the individual components into a functional circuit.13