The field effect transistor was patented in 1926 (https://en.wikipedia.org/wiki/Field-effect_transistor https://en.wikipedia.org/wiki/Field-effect_transistor) -

The field effect transistor was patented in 1926 (https://en.wikipedia.org/wiki/Field-effect_transistor https://en.wikipedia.org/wiki/Field-effect_transistor) - practical devices came later.