Reduction of the Linewidths of Deep Luminescence Centers inSi28Reveals Fingerprints of the Isotope Constituents

Abstract

Dramatic reductions of the linewidths of well-known deep centers in 28Si reveal "isotopic fingerprints" of the constituents. The approximately 1014 meV Cu center, thought to be either a Cu pair or an isolated Cu, is shown to contain four Cu atoms, and the approximately 780 meV Ag center is shown to contain four Ag. The approximately 944 meV ;{*}Cu center, thought to be a different configuration of a Cu pair, in fact contains three Cu and one Ag, and a new two-Cu two-Ag center is found. The approximately 735 meV center, previously assigned to Fe, actually contains Au and three Cu. This suggests a family of four-atom (Cu, Ag, Au) centers.

Deep electron traps and origin ofp-type conductivity in the earth-abundant solar-cell material Cu2ZnSnS4

“…Similar Cu clusters were proposed to exist in other semiconductor materials, such as silicon. 29,30 Because (Cu 2 ) Zn and (Cu 4 ) Sn are both fully compensated defects, they have no effect on the carrier concentration and recombination. Similarly, the low formation-energy defect pairs, such as Cu Zn +Zn Cu , are also fully compen-sated.…”

Isotopic fingerprints of Pt-containing luminescence centers in highly enrichedS28i

“…6,8 Pt at 60 keV with a dose of approximately 10 14 cm −2 . The implanted samples were annealed at 950°C for 10-30 min under flowing Ar to both remove the implantation damage and to allow the Au or Pt to diffuse into the bulk of the sample.…”

“…These results span the fields of shallow [1][2][3] and deep 4 impurity infrared-absorption spectroscopy, shallow bound exciton ͑BE͒ photoluminescence ͑PL͒ and photoluminescence excitation spectroscopy, 2,5,6 and deep center PL spectroscopy. [7][8][9][10] For the deep PL centers, often referred to as isoelectronic BE due to their relatively large PL efficiency compared to shallow donor and acceptor BE in Si, these reduced linewidths have resulted in a new and powerful method of characterizing the constituents of the binding center. [7][8][9][10] While isotope shifts have been an established method for the investigation and identification of such deep PL centers for many years, 11 the observed shifts of the PL lines have typically been smaller than the spectroscopic linewidths, revealing the participation of a given element in the center but not the number of atoms of that element.…”

“…[7][8][9][10] For the deep PL centers, often referred to as isoelectronic BE due to their relatively large PL efficiency compared to shallow donor and acceptor BE in Si, these reduced linewidths have resulted in a new and powerful method of characterizing the constituents of the binding center. [7][8][9][10] While isotope shifts have been an established method for the investigation and identification of such deep PL centers for many years, 11 the observed shifts of the PL lines have typically been smaller than the spectroscopic linewidths, revealing the participation of a given element in the center but not the number of atoms of that element. By making use of the dramatically narrower spectroscopic linewidth of no-phonon ͑NP͒ PL transitions in isotopically enriched 28 Si together with a highresolution spectrometer, PL peaks due to combinations of different isotopic masses of the constituents of a complex can be fully resolved, resulting in an "isotopic fingerprint" of the defect constituents.…”

Isotope engineering of silicon and diamond for quantum computing and sensing applications

“…[6] during its growth. A variety of dislocation-free, isotopically enriched 28 Si, 29 Si, and 30 Si crystals were grown at IKZ to fulfill orders placed by the Simon Fraser University, Canada, [35,36] the Keio University, Japan, [23,37] and the University of California (UC), Berkeley, CA, USA. [34,38] The third group of isotopically enriched, bulk Si crystals was grown at Keio University, Japan and will be referred to as the "Keio crystals".…”