ESR centers, interface states, and oxide fixed charge in thermally oxidized silicon wafers

Abstract

The ESR Pb center has been observed in thermally oxidized single-crystal silicon wafers, and compared with oxide fixed charge Qss and oxidation-induced interface states Nst. The Pb center is found to be located near the interface on (111) wafers. Its g anisotropy is very similar to that of known bulk silicon defects having SiIII bonded to three other Si atoms; the Pb unpaired electron orbital, however, is exclusively oriented normal to the (111) surface. The Pb center cannot be identified with any other known defect in Si or SiO2; in particular, it is totally unlike the common E′ center of SiO2. In contrast to Qss, both Pb and Nst were found to be greatly reduced by steam oxidation and hydrogen annealing. Both Pb and Nst may be regenerated by subsequent N2 anneals at 500 °C. In a graded series of samples, Pb and Nst are found to be proportional and nearly equal in concentration. This possible confirmation of SiIII at the interface, and correlation with Nst, support the theoretical indication of an SiIII band-gap energy level. The E′ center is unobservable, and if present, exists only in a concentration well below that of Qss. Thus, in addition to a lack of strong correlation with Pb, Qss is evidently not due to E′ centers in their normal charge state. Overall, ESR is judged to be a useful technique for research on silicon wafer defects.

Electrically Detected Magnetic Resonance of Donors and Interfacial Defects in Silicon Nanowires

“…In the last column the total number of P atoms in each wire is reported. [56][57][58] should dominate the spectrum. The g A and g B values obtained from the fit are, within the experimental error, identical to these values.…”

“…The first two signals are related to Pb 0 and Pb centers characteristics of the SiO 2 /Si(100) and SiO 2 /Si(111) interfaces respectively. [56][57][58] These interfaces are both produced by the anisotropic etching process followed by oxidation and lead to a superposition of several contributions from the g-matrix of the Pb 0 and the Pb centers. As depicted in Figure 3, Table I.…”

Influence of the Recombination Parameters at the Si/SiO2Interface on the Ideality of the Dark Current of High Efficiency Silicon Solar Cells

“…It is generally accepted that after annealing in forming gas or in hydrogen, the recombination centers at the Si/SiO 2 interface are uniformly distributed in the energy gap [9][10][11]. Hence D it (E t ) will be assumed to have a constant value D it .…”

Effects of hydrogenation on non-radiative defects in GaNP and GaNAs alloys: An optically detected magnetic resonance study

“…1,2 Well known examples of impurities/defects that can be efficiently passivated by hydrogen include B acceptors 3,4 and P donors 5 in Si, the V-O centers in Si and SiGe/Si heterostructures, 6,7 Be acceptors in AlGaAs/GaAs quantum wells (QW), 8 as well as silicon dangling bonds (P b defect) at a Si/SiO 2 interface. 9 In fact, the passivation of the P b defects is absolutely essential for reliable operation of metal-oxide-semiconductor fieldeffect-transistors, the heart of integrated circuit technology. In some rare cases, H was also found to activate defects and impurities such as Ga vacancy in GaAs (Ref.…”