An integrated circuit (IC) — colnironly called a chip is made out of’ a sew icondtlctor material called silicon, in which small e1ectrt›n ic components called transistors are lorlned within the silicon and then wired together with interconnects layered on top of the sit icon silrface. Integrated circuits are compact electronic chips made up of‘ interconnected components ihat include resistors. transistors, and capacitors. Bui lt on a single piece of’ semicondr1ctc›r material. such as silicon, integrated circuits can contain collections of’ hundreds to bil1ions of components — all working together to wake our world go round
Monolithic Integrated circuits:
Monolithic integrated circuits (lCs) are circuits in which lrultiple electronic components (e.g., transistors, capacitors, resistors, etc.) are integrated on a single silicon chip. Compared with traditional discrete components, monolithic integrated circuits have obvious advantages in terms of usage, size. power consumption, and rel iability. Monol ith ic integrated circuits can be divided into two types: digital integrated circuits and arising iniegrated circuits. Digital integrated circuits are mainly usea for ciig iiai systelrs. which are widely used in the fields of computers. communications. control, etc.. while analog integrated circuits are used for analog signal processing, which have many applications in the fields of"audio, video, and electricity
Hybrid Integrated circuits:
Hybrid integrated circuits (H lCs) are circuits that integrate difl'erent types of circuit components. such as analog circuits, digital circuits, RF circuits, etc. together to fol rn a single chip. Hybrid integrated circuits have the effect of both digital circuits and analog circuits. can process both digital and analog signals. Compared to monolithic integrated circuits, h\ bi id integrated circuits leave a higher deyrec of integration and a wider range of applications. Because hybrid iiltcyrated circuits can handle both analog and digital signals, they can be used in communication, radar, radio. audio and other fields
VLSI DESIGN:
Fabrication Process:
CMOS fabrication technology requires both N MOS and PMOS transistor to be built on the same cii ip subsiraic.
- To accommodate both NMOS & PMOS devices. special regions must be created in which the semiconductor type is opposite to the substrate type. These special regions are called wells or tubs.
- So, a n wcll is formed in a P substrate and a P well is formed in a n substrate. The simplified process sequence tor the fabrication of CMOS-
- The process starts with the creation of the n well regions for PMOS and p well regions for NMOS by ion implantation into the substrate.
- 1on in plantation is the process of‘adding in purities to a sil icon water.
- Then a thick oxide is grown th the regions surrounding the NMOS and PMOS active regions. The thin gate oxide is subsequently grown on the surface through thermal oxidation.
•Again a polysil icon layer is deposited old the surface of’ the oxide layers and selectively removed to toru the gate
