Hi
I attached a sheet that shows my doubts about MOSFETs.
It is used to say that to body doesn't matter that much in MOSFET analysis. I do not know why is this.
Later, in some books they refer the effect body (I didn't read yet about it, but must be for very accurate models. It seems (?) that body effects must be minor.. only being important in critical applications).
But my doubts are:
1 - If we apply a positive voltage in DRAIN (Vds) that has n+ (plenty of electrons ) is this turns out the n+ region in one p-region ?
2 - Why connecting a substrate(=body) terminal to the source terminal put the pn junctions reverse-biased!?! (see the sheet attached, please). And in this way they told that the body doesn't matter much in operation device??
3 - If really Vgs is turning out more positive and positive... it will pull down all holes to the base of the substrate and it has no anymore carriers - (no free electrons neither holes) causing a depletion layer.... the positive charges (from Vgs positive) will attract the negative charges to the other plater under gate... these negative charges comes from n+ drain and n+ source regions... forming a n-channel. But if this is so... how electrons then can travel in an one negative channel if they would be repealed again to the source (electrons will come from source to the drain in the current - provided that Vds is positive)? Please help me in these questions. If anything is not clear, ask me , I'll try to expose better my doubts.
ps English is not my native language, so sorry for any unclear sentence, or typos.
I attached a sheet that shows my doubts about MOSFETs.
It is used to say that to body doesn't matter that much in MOSFET analysis. I do not know why is this.
Later, in some books they refer the effect body (I didn't read yet about it, but must be for very accurate models. It seems (?) that body effects must be minor.. only being important in critical applications).
But my doubts are:
1 - If we apply a positive voltage in DRAIN (Vds) that has n+ (plenty of electrons ) is this turns out the n+ region in one p-region ?
2 - Why connecting a substrate(=body) terminal to the source terminal put the pn junctions reverse-biased!?! (see the sheet attached, please). And in this way they told that the body doesn't matter much in operation device??
3 - If really Vgs is turning out more positive and positive... it will pull down all holes to the base of the substrate and it has no anymore carriers - (no free electrons neither holes) causing a depletion layer.... the positive charges (from Vgs positive) will attract the negative charges to the other plater under gate... these negative charges comes from n+ drain and n+ source regions... forming a n-channel. But if this is so... how electrons then can travel in an one negative channel if they would be repealed again to the source (electrons will come from source to the drain in the current - provided that Vds is positive)? Please help me in these questions. If anything is not clear, ask me , I'll try to expose better my doubts.
ps English is not my native language, so sorry for any unclear sentence, or typos.
