Chapter 3, Current in Homogeneous Semiconductors

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Chapter 3, Current in Homogeneous Semiconductors

• Carrier Motion
• Current Flow
• Drift
• Diffusion
• Recombination/Generation
• Continuity Equations
• Use of Continuity Equations

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• Notation Reminder
• no, po equilibrium
• n, p general carrier concentrations

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Reference Pierret, Section 5.2
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Electrons added to condution band.
Electrons removed.
Holes removed.
Holes added to valence band.
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From nT/NT
no
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Note R corresponds to generation here!!
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Reference Pierret, Section 5.3.
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Equilibrium
Excess carriers
Gop is from light shining on the semiconductor
Normal recombination.
Depend on details of situation.
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For normal, low-level injection, pltltND
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For direct bandgap semiconductors, Rßnp for
direct band to band recombination.
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Minority carrier diffusion length for holes.
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