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The type-II InAs/GaSb superlattices (T2SLs)-based 640 × 512 long wavelength infrared (LWIR) Focal Plane Array (FPA) detector with15 μm pitch and 50% cut-off wavelength of 10.5 μm demonstrates a peak quantum efficiency of 38.6% and peak detectivity of 1.65 × 1011 cm Hz1/2 W−1 at 8.1 μm, high pixel operability of 99.5% and low responsivity non-uniformity of 2.69% at 80 K. The FPA exhibits clear infrared imaging at 110 K and diffusion-limited dark current densities below Tennant’s ‘Rule07’ at temperature above 100 K, which is attributed to the efficient suppression of diffusion dark current and surface leak current by introducing M-structure barrier and double hetero-structure passivation layers.

In order to precisely measure the ion parameters in a microwave electron cyclotron resonance plasma using an ion sensitive probe, the dependences of the current-voltage (I-V) characteristics on the shielding height (h) and the potential difference between inner and outer electrodes (VB) have been investigated at different working pressures of 0.03 Pa and 0.8 Pa. Results show that the I-V curves at higher pressure are more sensitive to the variation of h than those at lower pressure. The influence of VB on ion temperature (Ti) measurement becomes more prominent when the pressure is increased from 0.03 Pa to 0.8 Pa. Under both pressures, the optimized h is obtained at the condition where the current reaches zero in the positive voltage region with a suitable VB of −1.5 V because of effective shielding of the electron E×B drift.

Magnetoelectric heating was used to heat ions in an ECR plasma with a magnetic mirror field. The temperature and density of ions were measured by an ion sensitive probe (ISP) before and after magnetoelectric heating in order to investigate the influence of the anode ring's radius, axial position and working pressure on magnetoelectric heating. Results showed that a suitable radius of the anode ring could improve the ion temperature effectively and the optimal size of the anode ring depended on the cyclotron radius of ions. The radial uniformity of the ion density was improved by increasing the radius of the anode ring after heating. The magnetic mirror field could reduce the loss of ions caused by collision with the wall of the chamber and it was beneficial to increase the ion temperature and the ion density. It was suitable to heat the ions when the anode ring was set at the center of the magnetic mirror field where there was a weaker magnetic field strength. Lower pressure contributed to the increase in the ion temperature and efficiency of magnetoelectric heating.

The magnetoelectric heating is investigated on an ECR plasma device. The ion temperatures are measured by ion sensitive probe (ISP) before and after magnetoelectric heating. The influences of bias voltage of electrical ring, magnet field and pressure on ion temperature and the efficiency of ion heating are studied. The results indicate that the whole heating of the plasma is accomplished through the magnetoelectric heating of the ions in the sheath of the electric ring and the radial transport of the heated ions. The ion temperature in the axial area increases with the bias voltage of electric ring, and their relationship is nonlinear. The ion temperature increases more than 20 eV when the bias voltage is 1000 V. A heating efficiency is achieved to be as high as 2%2.5% and increases with the bias voltage increasing. The magnetic field strength plays an important role in the limitation and heating of the ions. The efficiency of the magnetoelectric heating increases with the increase of the magnetic field strength when the magnetic field strength changes from 6.310-2T to 8.710-2T. The efficiency of the magnetoelectric heating increases with the pressure decreasing when the pressure chenges in a range of 0.020.8Pa.