On a related matter - What does one mean by the diode being in a conducting state? If 1mA of current is a true conducting state what about 1uA? What about 1nA? Does a real diode ever not conduct in the forward bias direction with some non-zero forward bias applied?

It's a qualitative distinction and usually means that the currents are negligible either relative to the other currents in the circuit or relative to the current level that would be of significance for the situation at hand. The same with the forward voltage drop -- it's isn't some constant value yet we almost always assume that it is. Why? Because in most instances the change and also the error due to it not being exactly the assumed value are negligible for the application. If it isn't negligible, then we have to use a more complicated model.

 

Good reply, WBahn .

Like anything in physics, nothing is absolutely perfect. Electronic components are not perfect.

When we close the door to leave the house, for all practicable purposes it's shut. But it will never be rated 100% to be absolutely free of drafts and a perfect insulator against the outside environment.

Similarly diodes, transistors, etc. etc. all exhibit leakage currents, parasitic capacitance, etc. . . . . but so small they can be disregarded in many applications.

Also - We place semiconductor components into groups or categories based on their characteristic properties, much in the same way chemical compounds or elements are grouped and categorized (as in a periodic table).