{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Lecture 6 - Carrier Concentrations - Fermi Level - Drift

Lecture 6 - Carrier Concentrations - Fermi Level - Drift -...

This preview shows pages 1–3. Sign up to view the full content.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 1 EE360 – Lecture 64 Carrier Concentrations and Carrier Action • Objective: Be able to calculate carrier concentrations and currents in semiconductor devices. • Questions to be Answered: – Review and examples: How do we calculate carrier concentrations in practice? – How and why do we calculate the Fermi level? – How does drift describe carrier motion? EE360 – Lecture 64 Carrier Distributions and Concentrations: Review n-type material (more electrons than holes) intrinsic material (equal number of electrons and holes) p-type material (more holes than electrons) Pierret, p. 47 Pierret, p. 49 2 EE360 – Lecture 64 Carrier Concentration: Direct Approach • Integrate carrier distribution over the conduction band to find n and over the valence band to find p Integral of cond. band carrier distribution Integral of val. band carrier distribution Integrate Integrate Carrier Distribution Pierret, p. 50 Pierret, p. 47 EE360 – Lecture 64 Carrier Concentration: Direct Approach • Definition: effective density of states (does not depend on E ) • Non-degenerate assumption: – If E C- E F ≥ 3 kT and E F- E C ≥ 3 kT, then we say the semiconductor is non-degenerate kT E E kT E E C C F F C e e E f / ) ( / ) ( 1 1 ) ( − − ≈ + = Pierret, p. 51 Pierret, p. 52 3...
View Full Document

{[ snackBarMessage ]}

Page1 / 9

Lecture 6 - Carrier Concentrations - Fermi Level - Drift -...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online