SEMICONDUCTOR

Semiconductors constitute a unique category of materials exhibiting electrical characteristics that blend those of conductors and insulators. Analogous to a faucet regulating water flow, semiconductors offer precise control over electric currents.

Among semiconductors, the transistor holds paramount importance. In the early stages of modern electronics, integrated circuits featured a mere four transistors, enabling basic arithmetic operations. Presently, single chips accommodate billions of transistors.

The intricate process of integrating numerous transistors onto a minuscule chip, comparable in size to a fingernail, demands meticulous precision akin to dividing a strand of human hair into a thousand segments, each with specific width, and further subdividing each segment into a hundred parts. Consequently, semiconductor fabrication necessitates cutting-edge technological and scientific expertise

3. How are Semiconductors made?

• The process commences with an engineer meticulously selecting a silicon wafer as the base upon which the semiconductor will be constructed.
• A dedicated team subjects the silicon, derived from sand, to an elaborate purification procedure to isolate it from other substances, resulting in an ultra-pure wafer with impurity levels as minimal as a few parts per billion.
• This proportion is akin to an error margin of merely one centimeter when measuring the Earth's diameter.
• Subsequently, the photolithography process ensues—a pivotal stage wherein the circuit pattern is etched onto the wafer.
• The wafer is coated with a light-sensitive substance known as a photoresist. A mask is then positioned in front of the wafer, and light is directed onto it. The mask features small apertures corresponding to the circuit pattern.
• Light passes through these apertures, eroding the underlying sections of the photoresist. Consequently, the photoresist on the wafer adopts the configuration of the transistor circuits.
• After photolithography, engineers employ chemical and/or physical methods to eliminate the unetched portions of the photoresist, leaving the circuit's framework on the silicon substrate intact.
• Next, they introduce impurities into specific areas of the semiconductor—a process known as doping—to modify its electrical properties deliberately.
• Thin layers of materials such as metals or insulators are then deposited onto the wafer's surface to establish electrical connections or insulate components.
• Subsequently, the resultant product undergoes packaging—individual chips are segregated, encapsulated, and subjected to testing to ensure functionality and reliability—before integration into the electronic device