Hi All, I'm trying to understand how transistor works. I have drew some pictures for NPN transistor to show my current understanding. Can you please verify this for me. On the picture: "-" and "+" are movable charges; circled "-" and circled "+" are immovable ions. 1. No voltage applied. Two depletion layers are formed. 2. We apply voltage that we want to control - "-" to Emitter and "+" to Collector. Electrons from Emitter fill the Base forming negative ions. Electrons from Collector are gone; positive ions are formed in there. Because Base is filled with negative ions, electrons from Emitter can't go through - channel jammed. Here I'm not sure about Base-Emitter depletion layer - will there be any interaction between Base and Collector..? 3. We apply controlling voltage to Base. If we have BJT than we will have current between Base and Emitter, if we have FET, electrons inside of Base will be just pulled up, leaving positive charges behind. Electrons from Emitter will flow thought Base to Collector and will not be jammed again because Base is very thin. So, is my understanding correct? Do I do any mistakes..? Thank you!