From the brief survey on internet, I have come across a definition of technology node:
The half pitch distance between the metal 1 layers
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Further, for TSMC 65nm , the min. length is 60 nm
Till 250 nm node, the process node would be the min length possible.
Please clarify if this is correct. Kindly provide some authentic references
You want "correct", on stuff that's basically made up by Marketing
and becomes a sort of "consensus reality" by dint of everybody
blabbering about it circular fashion?
Technology node is the minimum available channel length in the process. 40 nm node means 40 nm transistor length available (may be only digital transistor)
65 nm means 65 nm length. If they have 60 nm length, they would have called it 60 nm node to sound better.
In the long past, the technology node used to be equal to minimum gate length (channel length), later one - to M1 half-pitch for DRAM version fo the technology, and starting from ~28nm node it is an abstract number that does not reflect the gate length at all.
Even different foundries have different node numbers to describe more or less the same technology node (e.g., 10 nm Samsung ~ 7nm TSMC).