Low-temperature formation of Mg/n-type 4H-SiC ohmic contacts with atomically flat interface by lowering of Schottky barrier height

To obtain an ohmic contact with a flat interface using a low-temperature process, we investigated the behavior of Schottky barrier height (SBH) at the Mg/n-type 4H-SiC interface to low-temperature annealing. Our results revealed that annealing at 200 °C reduced SBH; a low SBH of 0.28 eV was obtained on the lightly doped substrate. Atomic force microscopy measurements revealed negligible increase in the surface roughness after Mg deposition and annealing. Using the low-temperature process, a contact resistivity of 6.5 × 10−5 Ω⋅cm2 was obtained on the heavily doped substrate, which is comparable to Ni/4H-SiC subjected to annealing of above 950 °C.

Hexagonal Boron Nitride Passivation Layer for Improving the Performance and Reliability of InGaN/GaN Light-Emitting Diodes

We introduce a low temperature process for coating InGaN/GaN light-emitting diodes (LEDs) with h-BN as a passivation layer. The effect of h-BN on device performance and reliability is investigated. At −5 V, the leakage current of the h-BN passivated LED was -1.15 x 10−9 A, which was one order lower than the reference LED’s leakage current of −1.09 × 10−8 A. The h-BN layer minimizes the leakage current characteristics and operating temperature by acting as a passivation and heat dispersion layer. With a reduced working temperature of 33 from 45 °C, the LED lifetime was extended 2.5 times following h-BN passivation. According to our findings, h-BN passivation significantly improves LED reliability.

Water in bakery production technology products with delayed bakery

In bakery water is used as a solvent for salt, sugar and other raw materials: for dough preparation, preparation of liquid yeast, starter cultures; goes for household needs cleaning of raw materials, equipment, premises, for heat engineering purposes — the production of steam necessary to humidify the air in proofing cabinets and ovens. Water plays an important role in the technology of delayed baking of bread products or in the technology of frozen semi-finished products: it is used during kneading to obtain an optimally developed gluten frame for better form and gas holding capacity; to obtain cold dough, which is the basis for slowing down the onset of the fermentation process, while fermentation should be minimized or completely absent; the amount of water affects the consistency of the dough for better dimensional stability during defrosting. Also, a low-temperature process, deep freezing strongly affects the structural and mechanical properties of the dough and the quality of the finished product; secondly, under certain parameters of freezing, the structure of the intracellular water of yeast can lead to a decrease in their activity, and even to the death of microorganisms. Therefore, the issues of the quality and quantity of water at any technological operation in bakery production with delayed baking are issues of the quality of finished products and therefore are very relevant.