User:DeepDepletion

An engineer by trade, a physicist by training, and a writer by night.

Deep Depletion: a Metaphor
You would not be reading this or any other page on the WWW without the benefit of many billions of transistors, most of them of the MOS variety. These tiny devices are, in essence, electronic switches with no moving parts, made of a semiconducting material that can carry a current of negatively-charged electrons or of a positively-charged deficiency of electrons (ingeniously termed “holes”). The MOS switch happens when an electric field is applied to invert the carrier type, say from holes to electrons, in a channel, thus allowing current to flow between a pair of otherwise isolated islands of carriers. As the field is applied, the state of the channel changes from an accumulation of one type of charge carrier, to the depletion of both types, then to an inversion where the opposite type dominates, allowing a current to flow between the no-longer-isolated islands. In accumulation, the device is off. In inversion, the device is on. In depletion, the device is neither here nor there. If the electric field causing this change itself switches back-and-forth too rapidly, the channel doesn't have time to settle, comes to a state of deep depletion and is seriously neither here nor there. Kind of like my life, it seems.