On the nature of deep donors created at 450 °C in boron-doped p-Si

Abstract

It is shown that the boron impurity in oxygen-rich p-Si is involved in the formation of electrically active complexes, namely, d~~p thermal donors, during thermal annealing at T = 450 "C. The conclusion is based on experimental results obtained by several techniques such as Hall measurements, electron spin resonance, and photoluminescence. Ha OCHOBaHHEl 3KCIIePIIMeHTaJIbHbIX pe3yJIbTaTOB, lI0JIyseHHbIX IIpH H3Y9eHEl El CBOfiCTB Tep-MOO6pa6OTaHHOrO IIpH 450 "c KHCJIOpOnCOnepXa~erO p-Si(B) C HCIIOJIb30BaHHeM KOMlIJleKCa MeTORHK (3++eKTa XOJlJIa, 3nP H @OTOJIIoMHHeCIJeHIJHM), CneJIaH BbIBOn 0 TOM, 9 T O IIpHMeCb 6opa IIpH TaKHX OTXElraX y9aCTByeT B 06pa30BaHHH 3JIeKTpH9eCKH aKTHBHbIX KOMIIJIeKCOB -rny60~11x TepMOJ(OHOpOB.

Magnetic susceptibility of p-Si(B) single crystals grown in “vacancy” regime at presence of thermodonors created by thermal treatments at 450 °C

“…After preparation, the vacancy-type microdefects are usually dominant in these crystals. Beside doubly-charged TD-centers, the DTDs were also detected in this crystal [5]. In the crystals p-Si(B) grown at υ<υ cr (with the same amount of B and O impurities), the DTDs did not appear showing that presence of B and O is a necessary condition but insufficient to form DTDs.…”

“…Such behavior of the ESR spectrum in the initial and annealed samples can be explained by the appearance of ТD-centers with the ionization energy less than one of P impurity or when an acceptor B impurity is transformed into electrically nonactive state with increasing the annealing period. These hypotheses were successfully confirmed by using the low temperature photoluminescence method [5,7]. By analyzing the photoluminescence spectra in a non-ground region for the samples of p-Si(B) (crystal No.…”

“…To identify TD-centers and establish nature of DTDs which were detected in the samples p-Si(B) thermally treated at 450°C, the several adequate methods such as the Hall effect, ESR and low temperature photoluminescence were applied [5,7,8]. Let us remind two important results of these studies.…”

“…The relative error for MS measurements did not exceed 1 %. The Hall effect was studied in the initial and thermallytreated samples within the temperature range of 20 up to 450 K. In order to explain the MS results obtained, the experimental data more early published in [5,7,8] on the ESR spectra in the temperature range of 20-50 K and low temperature (at 4.2 K) photoluminescence for the investigated samples thermally annealed at 450 °C were used in this work.…”

“…In contrast, for the samples prepared from the crystals p-Si(B), grown in "vacancy" regime (at the speed of growth of υ = 2 mm/min > υ cr ), besides doublycharged TDs, the deep ТD-centers (DTDs) appear with the ionization energy Е і ≥ 200 meV [5]. Galvanomagnetic studies (Hall effect and temperature dependences n e = f (T)) along with measurements of ESR spectra and low-temperature (at 4.2 K) photoluminescence on the samples with DTDs enabled simply to establish that DTDs are singly-charged donor-centers which represent oxygen complexes containing one atom of boron [5]. Presence of deep singly-charged donorcenters DTDs with the ionization energy Е і ≥ 200 meV, which are in not ionized state within the range of 77-300 K, assists to study paramagnetic properties of these centers by the method of magnetic susceptibility even at room temperatures.…”