Extensive studies of the Emitter Dip Effect (EDE) in npn silicon structures are reported. Typically, 1 ohm‐cm n‐type silicon starting material was used. Boron diffusion into this material resulted in a 0.7μ base depth and surface concentrations of 1.8×1020 cm−3 . The emitter regions had surface concentrations of 3×1020 cm−3 and 0.4μ junction depths. The dip was typically 0.3μ, i.e., the base penetrated 0.3μ deeper under the emitter than elsewhere. Important experimental findings are: (A) Crucible grown, zone refined, and epitaxial silicon give the same results. (B) The EDE occurs only if phosphorus doping is sufficient to overcompensate the base doping. (C) Multiple emitter diffusion causes multiple dips. (D) Slow cooling from diffusion temperature enhances the dip. (E) An enhanced boron diffusion constant in the base layer apparently causes the dip rather than the rejection of boron by the region of high phosphorus concentration. (F) The dip is not present for lightly doped (1017 cm−3) base layers.

Measurement of transmitted phonon drag across 10 ohm cm ^>-type silicon indicates a phonon mean free path of the relevant thermal phonons which varies from about 80 n at 77°K to 12 /* at 250°K. The values depend on the method of evaluation. A simplified analysis suggests that below 150°K the longitudinal acoustic branch of the phonon spectrum is dominant.

The anodic dissolution of n-type Ge in aqueous solutions is generally assumed to be hole-production-rate limited.

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Carrier-removal rates produced in n- and p-type silicon by 1.7 MeV electron and reactor neutron irradiations were measured at 270°K on samples with resistivities between 0.1 and 50 Ω·cm. The measurements were performed under well-defined conditions on test samples selected from float-zone, quartz-crucible, Dash, and Lopex silicon crystals, and from epitaxial silicon slices. Most of the carrier-removal rates were determined from the initial 10% decrease in conductivity. Carrier-removal rates also were determined in heavily irradiated samples of float-zone and crucible-grown silicon. The electron-produced carrier-removed rate is strongly crystal growth dependent in n-type silicon, and the smallest removal rate is observed in quartz-crucible-grown material. The hole removal rate in p-type silicon under electron irradiation exhibits only weak crystal-growth dependence which becomes more pronounced during subsequent isochronal annealing. After 370°K annealing of both n- and p-type 10 Ω·cm materials, the smallest carrier-removal rate is observed in p-type Lopex silicon. Carrier-removal rates decrease with increasing electron fluence in both n- and p-type silicon. Neutron-produced carrier removal at 270°K is only weakly dependent upon crystal-growth method and conductivity type. Crystal-growth and conductivity-type dependence become significant, however, during subsequent isochronal annealing. After annealing to 370°K, the carrier removal remaining in n-type silicon is smallest for the crucible grown material, and the hole removal remaining in p-type silicon is smallest for the Lopex material. Carrier-removal rates increase with increasing carrier concentration and decrease with increasing neutron fluence in both n- and p-type silicon.