# How Jack Kilby Invented the First Integrated Circuit > Texas Instruments' 1959 patent for the first integrated circuit, which combined transistors and resistors on a single piece of semiconductor material. - **Patent:** US 3138743 - **Original title:** Miniaturized electronic circuits - **Owner:** Texas Instruments Inc - **Granted:** 1964 - **Status:** Public domain (expired) - **Times cited:** 27 - **Field:** semiconductors, consumer_electronics, mechanical ## What it does This patent describes the fundamental structure of an integrated circuit, or a microchip. It explains how to build multiple electronic components, specifically transistors and resistors, directly into a single wafer of semiconductor material like germanium or silicon. By layering regions of different electrical conductivity types—creating PN junctions—and connecting them with conductive paths on the surface, the design allows an entire circuit to exist on one small piece of material rather than using bulky, separate components wired together. This architecture is the ancestor of every modern processor. ## What it does NOT cover - Does not cover the use of non-semiconductor materials for building circuit components. - Does not cover vacuum tube-based circuit designs. - Does not cover specific manufacturing lithography techniques used to etch these patterns. - Does not cover multi-chip modules where separate dies are packaged together. ## The clever bit Kilby realized that if you could make a transistor on a semiconductor, you could also make a resistor or capacitor out of the same material, eliminating the need for external wiring between them. ## Real-world examples 1. The original Texas Instruments Solid Circuit 2. Early pocket calculators 3. Modern microprocessors 4. Memory chips ## Why it matters This is the 'Big Bang' of the modern computing era. Before this, engineers had to solder individual components together by hand, which was unreliable and limited how small a computer could be. This patent proved that complex electronics could be miniaturized, enabling the development of everything from pocket calculators to the smartphone in your hand. ## Frequently asked questions ### What does How Jack Kilby Invented the First Integrated Circuit cover? Texas Instruments' 1959 patent for the first integrated circuit, which combined transistors and resistors on a single piece of semiconductor material. ### Who owns patent US 3138743? Texas Instruments Inc owns this patent, granted in 1964. ### When does this patent expire? This patent has expired and is now in the public domain — anyone can use the invention freely. ### What is patent US 3138743 cited by? This patent has been cited by 27 later patents that build on its ideas. ### What problem does this patent solve? This is the 'Big Bang' of the modern computing era. Before this, engineers had to solder individual components together by hand, which was unreliable and limited how small a computer could be. This patent proved that complex electronics could be miniaturized, enabling the development of everything from pocket calculators to the smartphone in your hand. ### What does this patent NOT cover? Does not cover the use of non-semiconductor materials for building circuit components. **Full plain-English explainer:** https://patentbrief.org/patent/us/3138743/kilby-monolithic-integrated-circuit **Original patent:** https://patents.google.com/patent/US3138743 --- _Source: PatentBrief — https://patentbrief.org. Patent facts are from public records; the plain-English explanation is PatentBrief's._ ## Related patents Semantically similar inventions in the PatentBrief corpus: - [How Robert Noyce Invented the Modern Integrated Circuit](https://patentbrief.org/patent/us/2981877/noyce-planar-integrated-circuit) — Robert Noyce's 1959 patent for a semiconductor device that uses evaporated metal leads to connect components directly on a single silicon chip. - [How Texas Instruments Invented the Handheld Electronic Calculator](https://patentbrief.org/patent/us/3819921/barcode-upc-scanner) — This 1972 patent describes the architecture for the first truly portable, battery-powered electronic calculator that could fit in a pocket. - [The Invention of the Junction Transistor](https://patentbrief.org/patent/us/2569347/junction-transistor) — William Shockley's 1951 patent for the junction transistor, the fundamental building block of all modern digital electronics. - [The Invention of the Transistor](https://patentbrief.org/patent/us/2524035/point-contact-transistor) — Bell Labs' 1950 patent for the point-contact transistor, the fundamental electronic component that makes all modern computing possible. - [The Invention of the Modern Field-Effect Transistor](https://patentbrief.org/patent/us/3102230/mosfet-field-effect-transistor) — This 1960 patent describes the fundamental structure of the MOSFET, the tiny electronic switch that powers every modern computer processor.