VLSI Structure

The process of VLSI design involves several key stages

• System Specifications: Specifications of a system are the necessary items which should be considered and fulfilled to manufacture a device or design any system. These specifications cover the key details like IC size, current flow velocity, and the maximum permitted power consumption which meets the market requirements and the resources with minimum cost possible. It also describes the transistor performance and the working principle in a very simplified manner, hence providing a strong foundation for the design process.
• Architectural Design: This stage of finalizing architectural design determine its fundamental structure and concept. This involves choosing between RISC and CISC instruction sets which considers factors like power usage and performance needs. Teamwork across different departments will help the production of stronger and the most economical chip architecture.
• Functional Design: Functional design specifies the functionality of each unit within the VLSI design, ensuring seamless integration and operation. This phase optimizes chip design, identifies bottlenecks, and simplifies the fabrication process by providing clear guidelines. It plays a crucial role in error detection and debugging, rectifying any functional discrepancies early in the design process.
• Logic Design: Logic Design also known as Register Transfer level or Gate level description which involves expressing logic using hardware description language using Hardware description language such as Verilog or VHDL. It also addresses word widths, register allocation, control flow, arithmetic operations, and Boolean expressions for simulation and verification purposes. At the RTL level, the design concentrates on encapsulating digital components into registers and their transfers. Whereas the gate-level design delves into the implementation of logic gates and interconnections. Both levels serve as critical stages in the VLSI design process, offering different levels of abstraction and detail.
• Circuit Design: Circuit design develops the circuit representation based on the logic design, translating abstract concepts into physical circuits which involves specifying the arrangement and connection of circuit elements such as ICs, transistors, and diodes, to fulfill the functional requirements outlined in the logic design. Designers meticulously optimize the circuit layout to ensure efficient operation while meeting fabrication speed and power requirements. Also, this stage considers factors like signal integrity, noise immunity, and manufacturability to achieve a robust and reliable design.
• Physical Design: Physical design transforms the circuit diagram into a geometrical layout, translating abstract concepts into a concrete blueprint for fabrication. This intricate process involves precisely describing logic components and their interconnections using geometric models across multiple layers, ensuring optimal performance and manufacturability. It also include advanced layout synthesis tools that automates this complex process, facilitating design refinement and enhancing efficiency.
• Fabrication: Following layout construction, the design undergoes rigorous verification to validate its integrity and functionality before advancing to the fabrication stage. Now the fabrication stage begins after the design undergoes rigorous verification to validate its integrity and functionality. It involves the processing of high-purity silicon crystals to produce wafers, which serve as the foundation for semiconductor manufacturing. These wafers undergo polishing to achieve the required precision for chip production. Following the wafer polishing process, layout data is transformed into photo-lithographic masks, guiding the deposition of materials onto the wafer’s surface with utmost accuracy.
• Packaging And Testing: Post-fabrication, chips undergo packaging to safeguard their integrity and functionality while ensuring compliance with design specifications. Diverse packaging methods, tailoring to specific applications, are used to meet varied requirements. From aerospace to consumer electronics, bioelectronics to wireless communication, VLSI technology spans across multifaceted industries, reflecting its indispensable role in shaping the future of the electronics industry.

The field of electronics engineering comprises digital design and IC design, among others, that deal with the creation and optimization of electronic systems and components. Digital design particularly seeks to build computer circuits, such as binary logic circuits, manipulating digital signals. Such tasks include designing memory units, arithmetic circuits, and logic gates.

Whereas IC design stands for the development of intricate, small-sized electronic circuits, which are combined onto a single silicon chip. Digital circuitry and ICs are created, simulated, and tested with specific software tools and procedures for various applications, such as microprocessors, memory chips, and communication systems. The objective of these fields is to develop efficient and reliable electronic devices that meet performance, power, and cost requirements.