What is Punch-through?
A condition in which the source and drain depletion regions merge and current flows that the gate cannot control. It occurs when the channel is too short or the substrate doping is too low.
Field: MOSFET
Punch-through in the explanations
With a short channel and light substrate doping, the drain's depletion region can merge with the source's under drain bias, so current flows deep in the substrate independent of the gate and the device cannot turn off—punch-through.
Which correctly describes punch-through in a MOSFET?The trade-off is higher base resistance and a greater risk of punch-through, where the collector depletion region reaches the emitter, which limits breakdown voltage.
What is the main reason for making the base of a bipolar tr…A heavily doped layer of the opposite type at the fin base (a punch-through stopper) blocks this path.
In FinFETs built on bulk substrates, what is the purpose of…
Questions that mention Punch-through (5)
- Which correctly describes punch-through in a MOSFET?
- What is the main reason for making the base of a bipolar transistor thin?
- In FinFETs built on bulk substrates, what is the purpose of a heavily doped layer at the base of the fin (the part the gate controls poorly)?
- In CMOS well formation, what is a well called in which high-energy implantation makes the dopant concentration higher deep below the surface?
- What is the main purpose of halo (pocket) implants, which implant dopants of the same type as the channel at an angle near the source/drain edges?
Related terms
GAA (gate-all-around) Diffusion length Current gain (hFE) CMOS Retrograde well Latch-up Mobility Body effect Channel-length modulation DIBL