- #1
therash09
- 12
- 0
I am a beginner with respect to MOSFETs and have just begun studying them at college 2 weeks back.
What I am actually struggling with is the basic functional differences between MOSFETs and JFETs. Two of them are- dielectric and substrate, both of which are there in MOSFETs.
However, I don't understand much, the significance of having a dielectric, when I thought the direct application of a gate bias could have helped, though with opposite polarity.
Moreover, I don't understand why the term "junction" is used to describe the interface between Gate and Drain/Source?
And why do books talk about reverse/forward biasing these "junctions" when we know they are nothing but tiny overlaps of Gate over Drain/Source?
Do these tiny overlaps play such important role in MOSFET functioning or does it have something to do with the Substrate-Drain/Source junctions?
And, can't a substrate bias alone work without gate bias, as in the case of JFETs, where we have only one single voltage(gate) controlling the channel as input terminal?
Does a gate bias also control the substrate polarity, as the substrate bias does, but on the opposite face of the substrate?
These are a few initial doubts that I wanted to share. They might appear really stupid, but for me I know they're vital. If not cleared, they could snowball into a big trouble for me in the future.
So kindly reply...
Thankyou!
PS.:
This is not a homework question. Please don't mistake it for one!
What I am actually struggling with is the basic functional differences between MOSFETs and JFETs. Two of them are- dielectric and substrate, both of which are there in MOSFETs.
However, I don't understand much, the significance of having a dielectric, when I thought the direct application of a gate bias could have helped, though with opposite polarity.
Moreover, I don't understand why the term "junction" is used to describe the interface between Gate and Drain/Source?
And why do books talk about reverse/forward biasing these "junctions" when we know they are nothing but tiny overlaps of Gate over Drain/Source?
Do these tiny overlaps play such important role in MOSFET functioning or does it have something to do with the Substrate-Drain/Source junctions?
And, can't a substrate bias alone work without gate bias, as in the case of JFETs, where we have only one single voltage(gate) controlling the channel as input terminal?
Does a gate bias also control the substrate polarity, as the substrate bias does, but on the opposite face of the substrate?
These are a few initial doubts that I wanted to share. They might appear really stupid, but for me I know they're vital. If not cleared, they could snowball into a big trouble for me in the future.
So kindly reply...
Thankyou!
PS.:
This is not a homework question. Please don't mistake it for one!
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