At absolute zero (0 K), an intrinsic semiconductor behaves as:
**Semiconductor properties** distinguish from conductors and insulators by temperature dependence and doping response. At 0 K intrinsic acts as insulator, conductivity due to thermally generated electron-hole pairs, number of outer electrons 4 for Si/Ge forming covalent bonds, each atom shares electrons, crystal with N atoms has 4N valence electrons, 2N bonds. At 0 K, no thermal energy is available to excite electrons across the energy gap, so an intrinsic semiconductor has no free carriers and acts like an insulator. Substituting values gives Insulator, which matches expected behaviour for th
Ref: NCERT > Physics Book > Electronic Devices > Semiconductors, Types and Energy Bands