The effects of the ammonia-to-silane ratio, R, during deposition, and of postdeposition heating on chemically bound H in 1000A silicon-nitride films have been investigated using multiple internal reflection (MIR) spectroscopy. The films were deposited at 700~ with R equal to 10: 1, 100: 1, and 1000:1 in an Ar carrier gas. Vibrational modes for N-H and Si-H bonded centers show that H is incorporated into the films. The sum of the NH and Sill band intensities (total bound H) increased with R. The Sill band intensity, however, was largest in the 100:1 film. The increase in bound H with R is attributed to an increase in reactive H from NI% decomposition in the presence of incompletely bonded Si and N. The decrease in Sill centers when R is increased from 100:1 to 1000:1 is attributed to more complete Si-N bonding. Annealing behavior at 800~ suggests an initial transfer of H from N-H to Si-tt bonds in 10:1 and 100:1 films consistent with the presence of incompletely bonded Si. Bonding of implanted H in Si3N4 was demonstrated by isotopic substitution of D for H, and a calibration to determine H concentrations from MIR measurements was obtained. Bond energy-limited H loss is suggested to explain an observed mass-independent annealing for implantation-produced NH and ND centers.

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A simple two-layer model is presented for charge storage in a MI2I1S device in which the times for charging and discharging are expressed in closed-form expressions depending on the conduction properties, the thicknesses, and the dielectric constants of the two layers. Data were taken using silicon oxide for I1 and silicon nitride for I2 which are in good agreement with the model. The model is quite general and should be valid for other insulators and other conduction mechanisms.

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Metal silicon-nitride n-p+ silicon diodes have been fabricated with I-V characteristics similar to those of a four-layer diode. Switching between the two impedance states, whose impedance levels differ by a factor of the order of 106, can be accomplished in less than 5 nsec. The impedance of the device is controlled by the presence or absence of the inversion layer of the MIS structure. Both impedance states require a nonzero conductance of the insulator.