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Pre-silicon (theory)
Russell Ohl
1898-1987
Discovered the PN junction and the photovoltaic effect in silicon in 1940.
Contributions
- 01Bell Labs researcher who noticed a cracked silicon sample generated current in sunlight.
- 02Patented the first silicon solar cell and PN junction diode.
- 03His work created the physical basis for all diodes and transistors.
Why it matters for silicon physics
Without the PN junction you have no diode, no transistor, no logic gates. Every gigawatt datacenter starts with Ohl's 1940 observation of a cracked silicon ingot.