Solid-state ‘‘magic-angle’’ sample-spinning nuclear magnetic resonance spectroscopic study of group III–V (13–15) semiconductors

Abstract

We have obtained 27 Al, 69 Ga, 71 Ga, 113 In, and 115 In static and ‘‘magic-angle’’ sample-spinning (MASS) solid-state nuclear magnetic resonance (NMR) spectra of a series of polycrystalline III–V semiconductors (AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb, InN, InP, InAs, and InSb) at magnetic field strengths of 8.45 and 11.7 T. Line-broadening mechanisms have been identified by comparing static and MASS NMR results. By applying the MASS technique, dipolar, first-order quadrupolar, and pseudodipolar interactions are removed. Thus, the MASS spectral linewidth (of the central, 1/2↔−1/2, transition) is dominated by exchange and/or second-order quadrupolar interactions. For compounds having the cubic zinc blende structure, the exchange interaction dominates, and exchange interaction constants can be determined. For AlP, AlAs, AlSb, GaP, GaAs, InP, and InAs, first-order quadrupole effects are evident as spinning sidebands (SSBs), due to the satellite transitions. These effects are due to a small distribution of electric field gradients caused by lattice defects, and result in an overall Lorentzian profile for the SSB envelope. For compounds having the hexagonal wurtzite structure (GaN and AlN), the second-order quadrupolar interaction is the main line-broadening mechanism, and we find isotropic chemical shifts δi of 333 ppm [from 1 M Ga(NO3 )3 ] for GaN, and of 115 ppm [from 1M Al(H2 O)6 Cl3 ] for AlN, and nuclear quadrupole coupling constant e2 qQ/h of 2.8 MHz for 69 GaN, 1.7 MHz for 71 GaN, and of 2.2 MHz for AlN.

Optically pumped InP: Nuclear polarization from NMR frequency shifts

“…The hyperfine coupling is given a different symbol to indicate it is observed only during light irradiation; all other interactions are always observed. In the high temperature limit only H S 0 and H JS h can produce a frequency shift of the resonance, while all the interactions can broaden the NMR spectrum, with the In-P J-coupling and dipolar coupling dominating the phosphorus NMR line width [40][41][42][43][44] . At low spin temperatures, these interactions also have the potential to shift the resonance in addition to affecting the line …”

[Ga16(PtBu2)10]: ein mit Galliumphosphid ummantelter Kern aus vier nackten Ga‐Atomen?

“…B. a-Ga ca. + 4500 ppm) verschoben, [21] d. h. auch zu tieferem Feld als für kristallines GaP ( 69 Ga: + 307 ppm) beobachtet [22] wurde. Auch hinsichtlich der 31 PVerschiebungen gibt es zwischen 1 und festem GaP ( 31 P: + 146 ppm) [23] keine augenfälligen Parallelen.…”

Probing the Nitrogen Deficiency in Gallium Nitride by71Ga Magic-Angle Spinning NMR Spectroscopy

“…The chemical shift of the broad peak was temperature independent within experimental error. The broad peak had not been observed in the conversion of β-Ga 2 O 3 to GaN under a flow of ammonia below 1000 o C, 7 but was observed for samples nitridated at 1050 and 1100 o C for 3 h. Such a broad peak was observed for commercially available GaN powders, 9 but the peak has not been characterized yet in detail.…”

“…In the case of the sample nitridated at 800 o C for 3 h, there were no detectable peaks other than the peak at 325 ppm assigned to GaN. 9 With increasing the reaction temperature the peak of GaN became more narrow because of increase in crystallinity. It is interesting that there was also a broad peak at 425 ppm for the samples nitridated at 1000 and 900 o C for 3 h, though their XRD patterns show that they were GaN and a mixture of α-Ga 2 S 3 and GaN, respectively.…”