|3 Steps of Digitization, 2013|
This article takes a technology perspective and puts the development of digital technology on a timeline in 3 steps: vacuum, semiconductor, and digital electronic. The idea promoted in this note was prompted largely by a book called “the Journey of Electricity” by Derek Cheung PhD published in Chinese language in 2011 by BOOKZONE press in Taiwan.
Vacuum Step (1880 – 1950)
o Vacuum Tube was designed to get rid of the interference of air for conduction of electricity. Diode (1882) was a device that allowed electricity to flow in one direction only. Cathode Ray Tube was one good example of the application of diode in a vacuum tube. An iteration of diode was triode (1906). Triode has 3 terminals. The 3rd terminal controls the amplitude of electricity flow and acts as a switch as well. It was employed in many real life applications such as radio and computing. Indeed, the first computer was made solely with triodes in vacuum tube. ENIAC was commissioned in 1946 and it was made of 17468 triodes, drew 160kW of power to operate, and achieved 5000 add or subtract operations per second. ENIAC stands for Electronic Numerical Integrator and Computer.
Semiconductor Step (1940 – 2010)
o Semiconductor came to the front stage when we found that silicon with controlled impurity performed better than vacuum tube. Subsequently triode semiconductor called transistors (1948) kicked off the electronics age. Manufacturing technology took the driver seat from Material Science, and we came up with MOS (1960), CMOS (1963), Integrated Circuits, VLSI (1980), wafer, and System on Chip progressively. When Intel released the first microprocessor with 4 bits as in 4004 (1971), it consisted of 2300 transistors made on 10um conductor width and burned 1.2W of electricity only. Intel Ivy Bridge processors released in 2012 have billions of transistors and burn between 65W to 130W of electricity on 22nm conductor width. As miniaturisation gets close to the size of atoms, we will need to find a new concept to replace silicon as the building block.
Digital Electronic Step (1990 – 2060)
o Optical properties of semiconductors were realised such as Light Emitting Diode (LED), LASER and optical fibre up to 1970 when the first optical cable was laid across the Atlantic Oceans. MEMS for Micro Electro Mechanical Systems (1990) further extended electronics to mechanical motions and have been widely deployed in consumer devices such as smart phone and GPS navigator. Organic LED extends electronic to organic chemistry. Reversing OLED process can be used for energy generation. FPGA for Field Programming Gate Array is a device that allows programming of how the array should work on the spot. It is a new concept totally different to the Von Neumann computer architecture or Instruction Set Architecture (ISA) that dominated the world for the last 60 years. Digital electronics has become the building block of the modern age.