electron and hole mass

No, holes are real. Just as in a waiting line where sometimes "holes" form for various reasons when electrons move they can leave "holes" of positive charge(absence of electrons) that do exist. I don't like the use of the word hole as it can easily be misinterpreted and actually somewhat hides the true nature that is more confusion but should be understood.

These holes have mass in the sense of negative mass. That is, what mass would it take to "fill up" the hole.

In a waiting line the gaps move always towards the back and the people always move towards the front. If there is a gap that is formed then it might look like it is moving forward but if you just look at the fixed position of the gap and it will get filled by a person(but as that happens there is a gap formed in front of them by the person in front of them moving at the same time). We could ask what is the "mass" of a gap and it would be the number of people that could fit in the gap.

For a np junction you can ignore the concept of holes but it does require a little more thought. Since holes moving in one direction are equivilent to electrons moving in the opposite direction you can use either concept. The first one tends to be easier for most.

Jon

\\thanx a lot

This might be some help:

Mass is a measure of innertia, holes have innertia.

Bye. Jasen

Hole theory is as valid as electron theory. When an electron moves it leave a hole. Holes flow in opposite directions.