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Comprehensive overview of integrated circuits, their history, types, fabrication processes, advantages, and uses.

Introduction

  • Integrated circuits (ICs) are crucial inventions that have revolutionized technology, making devices more compact and capable.
  • Early computers were large, but ICs have enabled the development of smaller, more efficient devices.

Brief History

  • 1958: First integrated circuit (flip-flop using two transistors) built by Jack Kilby at Texas Instruments.
  • 2010: Intel Core i7 microprocessor with 2.3 billion transistors and 64 Gb Flash memory with over 16 billion transistors.

Transistor Revolution

  • 1947: Transistor invented by Bardeen at Bell Labs.
  • 1949: Bipolar transistor developed by Schockley.
  • 1956: First bipolar digital logic gate by Harris.
  • 1959: First monolithic IC by Jack Kilby.
  • 1960: First commercial IC logic gates by Fairchild.
  • 1962-1990s: TTL (Transistor-Transistor Logic).
  • 1974-1980s: ECL (Emitter-Coupled Logic).

Types of ICs

  • SSI (Small Scale Integration): Few tens of components per chip.
  • MSI (Medium Scale Integration): Hundreds of transistors per chip.
  • LSI (Large Scale Integration): Thousands of transistors per chip (e.g., 1KB RAM).
  • VLSI (Very Large Scale Integration): Introduced in the 1980s.
  • ULSI (Ultra Large Scale Integration), SOC (System On Chip), WSI (Wafer Scale Integration), 3D-IC (Three Dimensional Integrated Circuits): Modern complex devices.

Fabrication Processes

  • Silicon Wafer Preparation: Includes crystal growth, doping, ingot trimming, grinding, slicing, polishing, etching, and cleaning.
  • Epitaxial Growth: Growing a single crystal silicon structure on a silicon substrate.
  • Oxidation: Growing a silicon dioxide layer on the wafer surface for protection and impurity diffusion.
  • Photolithography: Producing small circuit patterns on silicon wafers using photographic masks and photo etching.
  • Diffusion: Introducing impurities into selected regions of the silicon wafer.
  • Ion Implantation: Controlled impurity introduction at low temperatures.
  • Dielectric Isolation: Using dielectric layers to electrically and physically isolate components.
  • Metallization: Producing thin metal film layers for interconnecting components on the chip, typically using aluminum.

Testing and Costs

  • Testing: Verifying operation of fabricated wafers using specialized probes and instruments.
  • Costs:
    • NRE (Non-Recurrent Engineering) Costs: Design time, mask generation.
    • Recurrent Costs: Silicon processing, packaging, testing, proportional to volume and chip area.

IC Packaging

  • Final stage of semiconductor device fabrication, encasing the semiconducting material to prevent damage and corrosion.
  • Types of packages: Metal can, dual-in-line, ceramic flat.

Advantages of ICs

  • Miniaturization, cost reduction, increased reliability, improved performance, matched devices, increased speeds, reduced power consumption.

Uses of ICs

  • Analog ICs: Power amplifiers, small-signal amplifiers, operational amplifiers, microwave amplifiers, RF and IF amplifiers, voltage comparators, multipliers, radio receivers, voltage regulators.
  • Digital ICs: Flip-flops, logic gates, timers, counters, multiplexers, calculator chips, memory chips, clock chips, microprocessors, microcontrollers.

Integrated Circuits – Lesson 15

Engineering Institute of Technology