Al thin films deposited by DC magnetron sputtering from two different target compositions on n-type Si(100) and SiO2 substrates were investigated as a function of substrate in-situ preheat temperature and ex-situ thermal annealing. Al grain size was increased when sputtered from Al-Si target composition compared to Al-Si-Cu Strong (111) texture of Al films on SiO2 substrate for both target composition and (101) texture when deposited on Si substrate were determined by EBSD method.
COBISS.SI-ID: 9074772
In this study we presented micro fabrication of silicon based fuel combustor with Pt/CeO2 catalyst. Ignition regimes for premixed methanol - O2 and methanol - air mixtures were studied. The obtained final temperature of the micro combustor strongly depends on the methanol partial pressure, residence time and the feed conditions. Autonomous combustor performance is demonstrated with an average liquid methanol feed rate of 1.45 ml h-1 at 320±2 °C.
COBISS.SI-ID: 9134420
In this work the system for reactive ion etching and mechanism of directional etching with SF6/O2 chemistry are described. Basic process parameters were investigated and results of etching were implemented into fabrication of silicon microstructures. A typical result of etching is: etch rate 1 to 2 µm/min, lateral undercut 5-6% in respect to the etch depth, aspect ratio less than 6 and selectivity to oxide and photoresist masks 100 and 20, respectively.
COBISS.SI-ID: 9312596
Electrical impedance measurements of the suspensions have to take into account the double layer impedance that is due to a very thin charged layer formed at the electrode-electrolite interface. A dedicated measuring cell that enables variation of the distance between the electrodes was developed for investigation of electrical properties of suspensions using two electrode impedance measurements. By varying the distance between the electrodes it is possible to separate the double layer and the suspension impedance from the measured data. From measured and extracted impedances electrical lumped models have been developed. The error of non inclusion of the double layer impedance has been analyzed. The error depends on the frequency of the measurements as well as on the distance between the electrodes.
COBISS.SI-ID: 9460564
Design, microfabrication process steps and characterization of catalytic microcombustors for three distinct energents (H2+O2, methanol+O2, methanol+air) built on (100) silicon-glass platform are presented. Thermodynamic properties, dependent on ignition parameters, light–off temperature and thermal response for various input flow conditions in the temperature range between 80-320 °C were investigated. It was determined that two-phase flow in microchannels can cause significant pressure oscillations which may degrade the performance of the microcombustor under certain feed conditions. Catalytic combusting via thin film nanodispersed Pt/CeO2 catalyst proved very efficient, showing light- off for combusting H2-O2 already at room temperature and in case of methanol-air combusting reagents at 80 °C. Assembled microcombustor was able to provide continuously 4.6 W thermal power, reaching the temperature of 290 ±1 °C, with 1.1 ml/h consumption of liquid methanol.
COBISS.SI-ID: 9595732