And while transistors may be regarded as humble now, because so many of the tiny semiconductors are used as switches or amplifiers in every electronic device, the impact of the invention would be difficult to overstate.
Kristof Beets, senior director of product management for PowerVR at Imagination Technologies, said: “The invention of the transistor led to the integrated circuit, the first of which contained just four transistors at 125 microns in size. Since those early days the technology has evolved exponentially and today, transistors are typically built on processes as small as 7nm – or 10 billionth of a metre.”
On 23 December 1947 two employees working at Bell Labs in the US state of New Jersey, John Bardeen and Walter Brattain, assisted by William Shockley, created the first working ‘point contact transistor’. The device was a forerunner of components that would replace the bulky, fragile vacuum tubes used at the time to amplify or switch electrical signals.
The first device was complex and fragile in appearance, but was quickly simplified for applications that required a smaller and more robust article.
Transistor becomes a television component
By the time Electronics Weekly was launched nearly 13 years later in September 1960 transistors had started to be built into consumer devices, such as the first portable TVs in the US, for instance. By the 1970s when this reporter had a part-time college job working on an electronics assembly line, transistors were small drawing-pin-sized three-pin devices that were plugged into perforated circuit boards for more expert engineers to connect by soldering wires between the transistor and other components.
Imagination Technologies has created a neat and informative timeline of the development of the transistor market (click on the image to enlarge it).
The dominant technology
In a book marking Electronics Weekly‘s 30th year of publication Leon Clifford wrote about Gordon Moore’s 1965 observation, later dubbed in the industry as ‘Moore’s Law’:
The number of transistors that can be crammed onto a microchip doubles every 18 months as the size of the transistor halves every three years. This continual remorseless shrinking process keeps the electronics industry in a state of perpetual revolution.”
Intel had already passed the one-million transistors-per-chip milestone by 1989.
And despite the passage of another 27 years since that publication and many forecasts of its imminent demise, a stretched version Moore’s Law still seems to apply: engineers are still doubling the component count of a microchip at regular intervals, with costs continuing to fall too.
Transistors by the billion
“Today, 10 million transistors could be placed in a pin head,” said Beets. “The typical smartphone boasts around 85 billion of them. The technology has transformed the world. It made the hearing aid a practical reality, transformed popular culture with the creation of the transistor radio and reduced the size of the computer from a whole room to something you can wear on your wrist.”
For consumer devices like the low-voltage radio chips used in a hearing aids, for example, up to 42 million transistors can be placed on less than 7mm2 of silicon.
And of course, GPUs delivering visual images of the quality and definition in displays that we have all come to take for granted have been a key beneficiary.
“No technology has leaned as heavily on the astonishing growth in transistor count as the GPU, enabling incredible levels of graphical performance within the power and area constraints placed on mobile devices,” said Beets, as he acknowledged Imagination’s debt to “the legacy of the amazing breakthrough by Bell Labs 70 years ago”.