In this biography
Quick facts
- Born
- 1924
- Died
- 1997
- Birthplace
- Switzerland
- Country
- United States
- Nationality
- Not independently established
- Known for
- Jean Hoerni developed the planar transistor process and helped build semiconductor companies that extended silicon-device manufacturing.
- Field
- Physicist and semiconductor entrepreneur
Why this life matters
Jean Hoerni developed the planar transistor process and helped build semiconductor companies that extended silicon-device manufacturing.
Timeline
Key moments
Physics and a new industrial setting
Jean Hoerni was born in Switzerland in 1924. He completed doctorates at Geneva and Cambridge before working at Caltech. In 1956 he joined Shockley Semiconductor Laboratory, entering an industrial setting where theories of semiconductor behaviour had to become manufacturable devices. The following year he became one of Fairchild Semiconductor’s founders. His career brought mathematical and physical training into close contact with the practical problems of materials, process conditions and reliability that could determine whether a young company’s products worked consistently.
Sources for this section: [1]
A protective layer becomes a process
Hoerni recorded an early planar concept in December 1957 and returned to it when exposed junctions created reliability problems. A 1959 disclosure and working transistor followed. The essential change was to retain silicon dioxide over sensitive junctions rather than remove it after masking. That protective surface made the transistor less vulnerable to contamination. The notebooks also distinguish this contribution from Noyce’s later use of an insulating layer and connections in an integrated circuit. Related inventions answered different problems within an evolving manufacturing system.
Further ventures and continuing manufacture
Hoerni left Fairchild in 1961 to help establish Amelco, then worked at Union Carbide before founding Intersil in 1967. These moves extended his work into new commercial organisations and device programmes. He died in 1997. His contribution lies in recognising that a layer treated as temporary could become an important permanent part of a device. The later companies show a career beyond that single insight, while the surviving process records make it possible to explain why his idea changed manufacturing without assigning every subsequent integrated-circuit advance to one person.
Quick answers
Frequently asked questions about Jean Hoerni
- What is Jean Hoerni known for?
- Jean Hoerni developed the planar transistor process and helped build semiconductor companies that extended silicon-device manufacturing.
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