Spin transport, magnetoresistance, and electrically detected magnetic resonance in amorphous hydrogenated silicon nitride

Abstract

We report on a study of spin transport via electrically detected magnetic resonance (EDMR) and near-zero field magnetoresistance (MR) in silicon nitride films. Silicon nitrides have long been important materials in solid state electronics. Although electronic transport in these materials is not well understood, electron paramagnetic resonance studies have identified a single dominating paramagnetic defect and have also provided physical and chemical descriptions of the defects, called K centers. Our EDMR and MR measurements clearly link the near-zero field MR response to the K centers and also indicate that K center energy levels are approximately 3.1 eV above the a-SiN:H valence band edge. In addition, our results suggest an approach for the study of defect mediated spin-transport in inorganic amorphous insulators via variable electric field and variable frequency EDMR and MR which may be widely applicable.

Review—Silicon Nitride and Silicon Nitride-Rich Thin Film Technologies: State-of-the-Art Processing Technologies, Properties, and Applications

“…In particular: • Stand-alone and embedded memory, due to its spin transport, magnetoresistance, and magnetic resonance properties. 47 • Protective layers/etch stops for metal lines and polysilicon structures, stabilization layers, and active device structures in MEMS. 26 • Antireflection coating and passivation layers in Si solar cells.…”

Extraction of isotropic electron-nuclear hyperfine coupling constants of paramagnetic point defects from near-zero field magnetoresistance spectra via least squares fitting to models developed from the stochastic quantum Liouville equation

“…EDMR accomplishes this through the measurement of EPRinduced changes in device current as a function of the magnetic field rather than a change in microwave absorption. The majority of EDMR studies have utilized one of two mechanisms: spindependent recombination (SDR) 8,[12][13][14][15][16][17][18][19][20] and spin-dependent trap assisted-tunneling (SDTAT) 9,[21][22][23][24] .…”

“…10 During a standard EDMR measurement, a change in current can also be measured when the magnetic field is swept through zero: the NZFMR response. [8][9][10]23,[25][26][27][28][29] The NZFMR response occurs with or without the presence of the oscillating magnetic field. The elimination of the oscillating magnetic field makes the measurement much simpler than conventional EPR and EDMR.…”

“…The small magnetic fields utilized in NZFMR also simplify the measurement. In some systems, the NZFMR response has been shown to closely scale with the amplitude of the EDMR response to the EDMR response in studies of device stressing 25 , radiation damage 10,23,29 , changes in temperature 26 and bias. 9,10,26 Although some analytical results have been extracted from the 6 NZFMR spectrum, no systematic approach has been available with which to obtain information on the strength of the interaction given a defined spin cluster.…”

“…In some systems, the NZFMR response has been shown to closely scale with the amplitude of the EDMR response to the EDMR response in studies of device stressing 25 , radiation damage 10,23,29 , changes in temperature 26 and bias. 9,10,26 Although some analytical results have been extracted from the 6 NZFMR spectrum, no systematic approach has been available with which to obtain information on the strength of the interaction given a defined spin cluster. We report on a systematic method to extract information about electron-nuclear hyperfine interactions from the NZFMR via a least squares fitting method.…”