Size of transistors?

Question

I want to know the size of the smallest transistor (the one we used to make processors for our laptop today) ?

And also how big the size of the earlier vacuum tube that ENIAC used ?

Answer 1

Ordinary dual triodes are about 1" in diameter and about 3 inches long.

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Answer 2

I know intel make consumer chips at transistors with a size of 45nm, don't know any smaller.

Answer 3

45 nm is the line width for the conduction channel of a MOSFET. That's how they specify transistor size now-a-days.  The acutal size of a typical MOSFET transistor is more like 60 nm x 80 nm = 4.8 fm^2 including part of the isolation wells.  The depth is about 20 nm.

Compare that with the OCTAL base tubes used in the ENIAC (9-pin mini's hadn't been widely used, then).  The base was about 1 1/4" in diameter and they were at least 3" tall.

You can fit 1.5 billion billion modern transistors inside a single tube of the ENIAC.

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