Physics - Solid State Physics - Semiconductors - intrinsic and extrinsic - Intrinsic and Extrinsic Semiconductors

4 sections. Section 1 'Intrinsic (pure) semiconductors': Silicon has Eg = 1.1 eV. At T=0: valence band full, conduction band empty (insulator!). At T>0: thermal energy excites electrons across gap. Each excited electron leaves a hole. n = p = nᵢ = AT^(3/2)e^(-Eg/2kT). For Si at 300K: nᵢ ≈ 1.5×10¹⁰ /