which transistor is invented first ?is it npn or pnp?

neither, it was a field effect transistor.

The first patent for the field-effect transistor principle was filed in Canada by Austrian-Hungarian physicist Julius Edgar Lilienfeld on October 22, 1925, but Lilienfeld published no research articles about his devices, and they were ignored by industry.

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A point-contact transistor was the first type of solid-state electronic transistor ever constructed.

It consisted of a germanium crystal placed on a metal plate. The germanium was of n-type with a p-type inversion layer. It operated as a PNP structure.

npn!

1947 - Invented by Bell Labs, in 1947, a transistor is a solid-state electronic device which is used to regulate the electricity flow. Basically, it is a semiconductor device which consists of three-four layers. Some basic functions like amplifying a signal or opening ...Invented by Bell Labs, in 1947, a transistor is a solid-state electronic device which is used to regulate the electricity flow. Basically, it is a semiconductor device which consists of three-four layers. Some basic functions like amplifying a signal or opening/closing a circuit is attributed to it. There are two types of standard transistors, NPN and PNP, with different circuit symbols.


Jan 23, 1948 - v4 page from Shockley's notebook documenting his conception of a "Semi-Conductor Valve," January 23, 1948. More than two years later, he added a note in the margin after such a device was successfully demonstrated. was an NPN sandwich instead of PNP, which ...v4 page from Shockley's notebook documenting his conception of a "Semi-Conductor Valve," January 23, 1948. More than two years later, he added a note in the margin after such a device was successfully demonstrated. was an NPN sandwich instead of PNP, which meant that electrons instead of holes had to serve as principal charge carriers. And it had electrical contacts attached directly to all three layers, which allowed much better control of the voltage levels in these ...


1964 - The configuration you see here with the emitters of an npn and a pnp connected in series is called a Rush Cascode, so named after an Englishman (I believe) called Christopher Rush, who devised this topology back in 1964

pin
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