Device Physics
Bands, doping, pn junctions, MOSFET, CMOS
01
·Device Physics·FREE·9 min read
MOSFETs from the Ground Up — A Sluice Gate Opened by Voltage, and the Reality of Leakage
The switch that fills every CPU and GPU, assuming no prior knowledge. From the sluice-gate analogy to threshold voltage, then the subthreshold leakage equation and why shrinking a transistor makes it leak more — the root of the power problem in one article.
02
·Device Physics·★ MEMBER·10 min read
Reading Chip Design as a Power Budget — The Physics of Leakage and Heat
A modern chip is limited not by what fits, but by how much of it can be lit at once. This piece reads that limit as a household budget: dynamic power versus leakage, the positive feedback that makes leakage swell with temperature, the thermal resistance that converts watts into degrees, and the three — and only three — ways a designer can spend the watts.
03
·Device Physics·FREE·11 min read
Band Theory from the Ground Up — Why It Had to Be Silicon
What actually separates a conductor from an insulator? Starting from why atomic energy levels smear into bands, this piece builds up bandgaps, Fermi statistics and doping with no prior physics assumed — and lands on the real answer to 'why is every chip made of silicon', which turns out to be about the oxide, not the element.
04
·Device Physics·★ MEMBER·9 min read
From FinFET to GAA — Why the Transistor Had to Go Vertical
Why did a flat transistor grow a fin, and then become a stack of thin slabs? With three tools — short-channel effects, DIBL, and the natural length — this piece shows that FinFET and GAA nanosheets were not a matter of taste but a corner physics painted the industry into. No prior knowledge assumed.
05
·Device Physics·★ MEMBER·12 min read
The Physics of NAND Flash — Remembering by Trapping Electrons
Why does a memory stick keep your photos with the power off? Starting from one idea — trap electrons on an island of insulator and shift a threshold voltage — this article builds up tunnelling writes, multi-level cells, 3D stacking and wear-out, and ends where you can read an SSD datasheet and a SMART log for yourself.