process technology

process technology

The particular manufacturing method used to make silicon chips, which is measured by how small the transistor is. The driving force behind the design of integrated circuits is miniaturization, and process technology boils down to the never-ending goal of smaller. It means more computing power per square inch, and smallness enables the design of ultra-tiny chips that can be placed almost anywhere.

Feature Size Measured in Nanometers
The size of the features (the elements that make up the structures on a chip) are measured in nanometers. A 22 nm process technology refers to features 22 nm or 0.022 µm in size. Also called a "technology node" and "process node," early chips were measured in micrometers (see table below).

Historically, the feature size referred to the length of the silicon channel between source and drain in field effect transistors (see FET). Today, the feature size is typically the smallest element in the transistor or the size of the gate.

From 1,000 Down to 90
The feature size of the 486 chip in 1989 was 1,000 nm (one micron). By 2003, it was 90 nm, reduced by a little less than one millionth of a meter. What may seem a minuscule reduction took thousands of man years and billions of dollars worth of R&D. In the table below, note the dramatic reductions in the early years of semiconductors.

It May Not Always Smaller
In the semiconductor industry, the goal has always been to pack more transistors on the same square millimeter of silicon. At any given time, the smallest feature sizes are found on the latest, high-end CPU and SoC chips that cost several hundred dollars. However, 8-bit and 16-bit microcontrollers (MCUs) are used by the billions and sell for only a couple dollars. They have far fewer transistors and do not need to be so dense. A USD $2 microcontroller may have feature sizes similar to the high-end chips a decade or two earlier. See microcontroller, CPU and SoC.

A Miracle of Miniaturization
To understand how tiny these transistor elements are, using 10 nm feature sizes as an example, eight thousand of them laid side-by-side are equal to the cross section of a human hair. See half-node and active area.

From 120,000 to 5 Nanometers
In the late 1950s, a fraction of a millimeter might have seemed tiny; however, by 2020, feature size was reduced from 120,000 nm to 5 nm.

Semiconductor Feature Sizes(approximate for all vendors)      Nanometers  Micrometers  MillimetersYear     (nm)       (µm)       (mm)

 1957  120,000      120.0       0.12
 1963   30,000       30.0       0.03
 1971   10,000       10.0       0.01
 1974    6,000        6.0
 1976    3,000        3.0
 1982    1,500        1.5   **
 1985    1,300        1.3   **
 1989    1,000        1.0   **
 1993      600        0.6   **
 1996      350        0.35  **
 1998      250        0.25  **
 1999      180        0.18  **
 2001      130        0.13  **
 2003       90        0.09  **
 2005       65        0.065
 2008       45        0.045
 2010       32        0.032
 2012       22        0.022
 2014       14        0.014
 2017       10        0.010
 2018        7        0.007
 2020        5        0.005
 2022        3        0.003

 Future
 Non-Silicon
 Method      1        0.001

 ** Still used for MCUs that do not
    require state-of-the-art
    technology (see  microcontroller).

Half a Micron Is Huge

In a span of five years throughout the 1990s, the feature size of these earlier AMD chips was reduced from .8 to .35 micrometers. Half a micrometer may seem insignificant, but not in the microminiature world of semiconductor manufacturing. That difference represents 450 nanometers. As features get smaller, the chip runs faster and uses less energy to execute instructions. (Trans = transistors). (Image courtesy of Advanced Micro Devices, Inc.)

Copyright © 1981-2019 by The Computer Language Company Inc. All Rights reserved. THIS DEFINITION IS FOR PERSONAL USE ONLY. All other reproduction is strictly prohibited without permission from the publisher.