A high-visibility infrared array emitter for identification and display screen has been demonstrated. The silicon-based MEMS Infrared emitter was fabricated on silicon-on-insulator (SOI) wafer. The infrared emitter cell can be operated at 1100K with a total power of 2.5W, and the modulation frequency can reach to 50Hz at 50 modulation depth. The Infrared array emitters consist of 1*2, 2*2 and 3*3 emitter cells, respectively, which can be made as an infrared indicator or display screen for object identification and information displaying with a recognition ranges determined by input power. The experiments shown that due to the problems of structure and stress, the modulation frequency and lifetime of the infrared array emitter were reduced with increasing array dimension.
In spin electronic devices, passing a spin-polarized current through the device is a better way to switch the magnetic
configuration than applying an external magnetic field with an external current line, because there are several drawbacks
associated with the use of external magnetic fields in terms of energy consumption and the risk of crosstalk. One good
method is using a current to induce domain wall motion from a constriction in a spin-valve structure, which generates
much interest in the case of spin-dependent electron transport across a nanocontact or a nanoconstriction. The samples
are fabricated on a SiO<sub>2</sub>/Si substrate using electron beam lithography and a lift-off technique. Electron beam lithography
was used to define the nanocontact structure and radio frequency magnetic sputtering with pure Ar was used to deposit
an Al<sub>50</sub>Fe<sub>50</sub> alloy layer about 30 nm thick and an Au cap-layer about 2 nm thick. Ultrasonic assisted lift-off in acetone is
used to obtain the wire and the constriction. The I-V measurement is performed at room temperature without applied
magnetic field. A sharp drop in resistance was observed in the 50-nm-wide nanocontact, which is attributed to the
removal of the domain wall from the contact by the reflection of spin polarized electron. In the low resistance state, no
domain wall is pinned at the contact, while in the high resistance state the presence of a domain wall must be responsible
for the additional resistance, which is the domain wall resistance.
RF MEMS capacitive switches hold great promise in commercial, aerospace, and military applications. However,
their commercialization is hindered by reliability concerns: charging effect in the dielectric layer can cause irreversible
stiction of the actuating part of the switch. Presently, a popular method to investigate the charging/discharging in the
dielectric layer is to measure an actual RF MEMS capacitive switch, which means a high experimental cost in fabricating
MEMS switch devices.
In this paper, a Metal-Insulator-Semiconductor (MIS) capacitor is used to investigate the charge accumulation in
the dielectric layer of RF MEMS switches. By measuring the capacitance versus voltage (C-V) curves of MIS capacitor
after voltage stressing, the dielectric charging/discharging characteristics are obtained. The experiment results indicate
that the injected charges from the metal bridge in RF MEMS switches are responsible for stiction phenomena. In SiNx
dielectric, the hole capture is more favored over electron capture, and the trapped charges tend to inhibit the charges
further injecting. The effects of the actuation voltage waveform on the charge accumulation in the dielectric layer were
investigated. It is verified that the tailored actuation voltage waveforms can be used to improve the reliability of RF
MEMS capacitive switches.