A spin-polarized vertical-cavity surface-emitting laser is demonstrated with electrical spin injection from an $\mathrm{Fe}/{\mathrm{Al}}_{0.1}{\mathrm{Ga}}_{0.9}\mathrm{As}$ Schottky tunnel barrier. Laser operation with a spin-polarized current results in a maximum threshold current reduction of 11% and degree of circular polarization of 23% at 50 K. A cavity spin polarization of 16.8% is estimated from spin-dependent rate equation analysis of the observed threshold reduction.

A common framework for interface-trap (N _IT ) generation involving broken equivSi-H and equivSi-O bonds is developed for negative bias temperature instability (NBTI), Fowler-Nordheim (FN), and hot-carrier injection (HCI) stress. Holes (from inversion layer for pMOSFET NBTI, from channel due to impact ionization, and from gate poly due to anode-hole injection or valence-band hole tunneling for nMOSFET HCI) break equivSi-H bonds, whose time evolution is governed by either one-dimensional (NBTI or FN) or two-dimensional (HCI) reaction-diffusion models. Hot holes break equivSi-O bonds during both FN and HCI stress. Power-law time exponent of N _IT during stress and recovery of N _IT after stress are governed by relative contribution of broken equivSi-H and equivSi-O bonds (determined by cold- and hot-hole densities) and have important implications for lifetime prediction under NBTI, FN, and HCI stress conditions

Negative bias temperature instability (NBTI) is studied in plasma (PNO) and thermal (TNO) Si-oxynitride devices having varying EOT. Threshold voltage shift (DeltaV_T) and its field (E_OX), temperature (T) and time (t) dependencies obtained from no-delay on-the-fly linear drain current (I_DLIN) measurements are carefully compared to that obtained from charge pumping (CP). It is shown that thin and thick PNO and thin TNO devices show very similar NBTI behavior, which can primarily be attributed to generation of interface traps (DeltaN_IT). Thicker TNO devices show different NBTI behavior, and can be attributed to additional contribution from hole trapping (DeltaN_h) in pre-existing bulk traps. A physics based model is developed to explain the experimental results.

We have developed a double-channel high electron mobility transistor with back barriers for carrier confinement. We have observed that the double-channel devices may suffer from the lack of gate control particularly for the lower channel. However, the problem can be contained by using a suitable back barrier for the lower channel. The double-channel back-barrier devices show good current gain and power gain cutoff frequencies. These devices can be operated with excellent gain linearity up to a larger value for input power and frequency.

Negative bias temperature instability (NBTI) is studied in p-MOSFETs having decoupled plasma nitrided (DPN) gate oxides (EOT range of 12 Aring through 22Aring). Threshold voltage shift (DeltaV_T) is shown to be primarily due to interface trap generation (DeltaN_IT) and significant hole trapping (DeltaN_OT) has not been observed. DeltaV_T follows power-law time (t) dependence and Arrhenius temperature (T) activation

The high-frequency dynamics of spin-polarized carriers and photons in a spin laser have been studied. The transient response of the device obtained from the rate equations is characterized by two sets of relaxation oscillations in the carrier and photon distributions corresponding to the two polarization modes. Consequently two distinct resonant peaks are observed in the small-signal modulation response. The calculated transient characteristics indicate that the best results are obtained from a spin laser when only the favored polarization mode, with lower threshold, is operational. Under this condition the small-signal modulation bandwidth is higher than that in a conventional laser, the threshold current is lower and the output polarization can be 100% with appropriate bias conditions, independent of the spin polarization of carriers in the active region. Measurements were made at 230 K on a InAs/GaAs quantum dot spin vertical cavity surface emitting laser. A time-averaged output polarization of 55% is measured with an active region spin polarization of $5–6\mathrm{\%}$. The experimental results are in good agreement with calculated data.