On the Effect of Lead on Irradiation Induced Defects in Silicon

Abstract

Different group IV impurities (Pb, C, and Sn) have been introduced in the melt during the growth of n-type Czochralski silicon. The samples have been irradiated with 1 MeV electrons to a fluence of 4x1015cm-2. The irradiation-induced defects have been studied by Deep Level Transient Spectroscopy (DLTS). It is shown that the formation of one of the irradiation-induced deep level is avoided by the Pb-doping. This level is located at 0.37 eV from the conduction band edge (EC) and shows an apparent capture cross-section of 7x10-15cm2. In addition, another irradiation induced deep level located at EC - 0.32 eV has been studied in more details.

Doping strategies to control A-centres in silicon: insights from hybrid density functional theory

“…24,25 Additionally, given that the -2 charge state of GeVO dominates under n-type conditions, see Fig. 3, doping with Ge can be problematic.…”

Controlling A-center concentration in silicon through isovalent doping: mass action analysis

“…38,53,54 Nevertheless, introducing further C in the lattice can lead to more C-related defects that can be in turn deleterious for the properties of Si. 50,55 Conversely, Sn doping at around does not require codoping with C and therefore given its similar efficiency with Pb at reducing VO defects it is a better choice.…”

Vacancy-oxygen defects in silicon: the impact of isovalent doping

“…In any case, although the effect of lead in radiation induced defects has been studied as systematically as Ge or Sn, it has been found [98,[105][106][107]146,147] that Pb, mostly in codoping with C to relieve the strains in the lattice, suppresses the formation of the VO defect, affects its thermal stability and reduces its conversion to the VO 2 defect. Additionally, it has been determined [20,148] that Pb has an influence on the density of growth of microdefects and on the lifetime of non-equilibrium current charge carriers, as well as on the formation of thermal donors and oxygen precipitates.…”

“…C codoping with Pb in Si has been used [160] to retain the Pb atoms at substitutional sites and suppress any Pb precipitation in the Si lattice [161]. Also, Pb and C codoping suppresses VO formation more than with Cdoped Cz-Si [105][106][107]146,147] …”