Semiconductor carrier freeze-out
= Semiconductor carrier freeze-out
At sufficiently low <temperature>, thermal ionization of shallow dopants becomes inefficient, reducing the mobile <carrier density>. An acceptor-doped sample may then have many neutral acceptors and few mobile <electron holes>. Extracting an activation <energy> requires a model of dopant ionization and compensation; the mobile density need not have the same simple activation exponent in every compensation regime.