Summer 1958, Texas Instruments, Texas.
Most employees had gone on vacation; the office was empty. But a new engineer was still sitting in the lab, thinking about a problem.
He was Jack Kilby, who had joined the company just months earlier. Being junior, he had no vacation time and had to stay in the lab.
“Since I have time,” he thought, “why not try that idea.”
That idea was: Could an entire circuit be made on a single piece of material?
At the time, circuits consisted of transistors, resistors, capacitors, and other components, each manufactured separately and then connected with wires. The components themselves were small, but packaging and wiring took up most of the space.
Kilby thought: If all components were made on the same piece of semiconductor material, packaging and wiring could be eliminated.
He began experimenting.
Kilby’s Experiment #
Kilby used a piece of germanium wafer and made transistors, resistors, and capacitors on it. Then he connected them with thin gold wires.
On September 12, 1958, he demonstrated this device to company executives.
“What is this?” someone asked.
“This is a phase-shift oscillator,” Kilby said. “It integrates all circuit components on a single piece of germanium.”
Power was applied, and a perfect sine wave appeared on the oscilloscope.
The world’s first integrated circuit was born.
It was only half an inch long with 5 components. But its significance was revolutionary: proving that “making an entire circuit on a single piece of material” was feasible.
Noyce’s Improvement #
Meanwhile, at Fairchild Semiconductor in California, another person was thinking about the same problem.
He was Robert Noyce, one of the “Traitorous Eight” and co-founder of Fairchild Semiconductor.
Noyce heard about Kilby’s invention but found a problem: Kilby’s integrated circuit used gold wires to connect components, which still wasn’t reliable enough.
Noyce came up with a better approach: Use planar process to make connections on the silicon surface too.
He used Fairchild’s planar process to create metal wires on the silicon surface, connecting components. This way, the entire circuit—transistors, resistors, capacitors, wires—was all on the same silicon chip, requiring no external connections.
In 1959, Noyce filed for the integrated circuit patent.
Who Was the Real Inventor? #
Kilby and Noyce—who was the true inventor of the integrated circuit?
This question sparked a decade-long patent battle.
Finally, the court ruled: Both were independent inventors, sharing the invention rights for integrated circuits.
Kilby invented the first working integrated circuit, proving the concept’s feasibility. Noyce invented the mass-producible integrated circuit, solving the manufacturing problem.
In 2000, Kilby received the Nobel Prize in Physics. Noyce had died in 1990 and couldn’t receive the award (Nobel Prizes aren’t awarded posthumously).
In his acceptance speech, Kilby said: “If Noyce were alive, he would be standing here with me.”
Advantages of Integrated Circuits #
Why are integrated circuits important?
First, small size. Components that previously needed an entire circuit board can now fit on a fingernail-sized chip.
Second, low cost. Integrated circuits can be mass-produced; one photolithography can make hundreds or thousands of transistors. Costs are much lower than manufacturing and assembling components separately.
Third, high reliability. No external connections means no connection failures. Integrated circuit failure rates are several orders of magnitude lower than discrete component circuits.
Fourth, high speed. Components are closer together, signals travel faster. Integrated circuit speeds are much higher than traditional circuits.
Fifth, low power consumption. Smaller components and shorter distances mean lower power consumption.
These combined advantages made integrated circuits the core of electronic devices.
From Small Scale to Ultra Large Scale #
Integrated circuit development went through several stages:
SSI (Small Scale Integration): A few to dozens of transistors per chip (1960s)
MSI (Medium Scale Integration): Hundreds of transistors per chip (early 1970s)
LSI (Large Scale Integration): Thousands to tens of thousands of transistors per chip (mid to late 1970s)
VLSI (Very Large Scale Integration): Hundreds of thousands to millions of transistors per chip (1980s)
ULSI (Ultra Large Scale Integration): Tens of millions to billions of transistors per chip (1990s to present)
Today, the most advanced chips have hundreds of billions of transistors. Apple’s M3 Ultra chip has 134 billion transistors; NVIDIA’s B200 has 208 billion.
From Kilby’s 5 transistors to today’s hundreds of billions—a 20 billion-fold increase.
Intel and the Microprocessor #
In 1968, Noyce and Gordon Moore left Fairchild and founded Intel.
In 1971, Intel introduced the 4004—the world’s first commercial microprocessor. It was a complete CPU integrated on a single chip.
The 4004 had 2,300 transistors, a clock frequency of 740kHz, and could perform 4-bit operations. Its performance was less than ENIAC’s, but it was one-millionth the size.
The birth of the microprocessor shrank computers from room-sized to desktop-sized, and eventually to pocket-sized.
Chip Manufacturing: Humanity’s Most Precise Craft #
Chip manufacturing is the world’s most precise manufacturing process.
Photolithography is the core step: using light to “print” circuit patterns onto silicon wafers.
The smaller the circuit pattern, the more transistors on the chip, the stronger the performance. Today’s advanced chips have transistor spacing of just a few nanometers—about one ten-thousandth the width of a human hair.
To make such tiny patterns, lithography machines use extreme ultraviolet (EUV) light with a wavelength of only 13.5 nanometers. One EUV lithography machine is as big as a bus and costs over $150 million.
Currently, only the Dutch company ASML can manufacture EUV lithography machines. This is the crown jewel of human industry.
The Impact of Integrated Circuits #
Integrated circuits changed the world:
Computers: From room-sized to desktop-sized, then to laptops, tablets, phones.
Communications: Mobile phones, base stations, satellites all rely on integrated circuits.
Medical: Pacemakers, medical imaging equipment, gene sequencers.
Transportation: Automotive electronics, aircraft control systems, autonomous driving.
Entertainment: Game consoles, smart TVs, VR devices.
Infrastructure: Power grid control, financial systems, the internet.
Today, almost every industry in the world relies on integrated circuits. Without chips, modern life would stop.
Next Step: Moore’s Law #
The development of integrated circuits can be described by one law.
In 1965, Gordon Moore observed: The number of transistors on an integrated circuit doubles every 18-24 months.
This observation later became known as Moore’s Law.
It predicted the exponential growth of computer performance and guided the semiconductor industry for decades.
The story of Moore’s Law continues tomorrow.
Today’s Key Concepts #
Integrated Circuit (IC) A circuit that integrates multiple electronic components (transistors, resistors, capacitors, etc.) on a single semiconductor substrate. Also called a “chip.” Integrated circuits greatly reduced the size of electronic devices, improved reliability and performance, and lowered costs.
Photolithography The core process of chip manufacturing. Light projects circuit patterns onto silicon wafers coated with photoresist, then chemical methods etch the circuit structures. Photolithography precision determines the size and number of transistors on a chip.
Microprocessor A CPU with all functions integrated on a single chip. In 1971, Intel introduced the 4004, the world’s first commercial microprocessor. The birth of microprocessors marked computers entering the personal era.
Discussion Questions #
- Integrated circuits made electronic devices smaller, cheaper, and more reliable. Which of these three advantages do you think had the biggest impact on ordinary people’s lives?
- Today’s chips have hundreds of billions of transistors. Can you imagine how such tiny things are manufactured?
Tomorrow’s Preview: Moore’s Law—how did Intel’s founder predict the exponential growth of computer performance?