Vol 46, No 1 (2017)

The peculiarities of photoresist etching in inductively coupled plasma in various modes, including the mode using to etch the GaN-based structures are investigated. The continuous in situ monitoring of the photoresist thickness, surface morphology, and substrate temperature was performed with the help of the optical reflectometry and low-coherent interferometry. It is shown that the etch rate of photoresist is not constant but decreases in the course of the process, which is in addition associated with the substrate heating. It is revealed that the pulsed etching mode makes it possible to exclude the development of the roughness observed in the continuous mode. The comparison of the new data with the etch rates of the photoresist with the characteristic rates of GaN etching performed under the same conditions made it possible to determine the process parameters and photoresist thickness necessary to perform the mentioned etching process in the optimal mode.

The interaction between carbon nanotubes and alloying impurities was analyzed and the thermodynamics of controlling the properties of carbon nanotubes was developed. The analysis of the experimental and theoretical data showed that the free energy of the gas mixture in the reactor and the temperature of the reactants play a dominant role in alloying and adsorption. The thermodynamic parameters of alloying carbon nanotubes with hydrogen, oxygen, nitrogen, and boron impurities were calculated.

A comparison of the efficiencies of the power supplies produced based on the β-radiation sources has been carried out. The factors decreasing the efficiency of the device have been revealed. The results of the experimental studies and calculations of the efficiency of the direct energy conversion of Ni-63 β-radiation into electrical energy using silicon p–i–n diodes are presented. An expression for the open-circuit voltage of the convertor taking into account the distribution of high-energy electrons in the space charge region (SCR) of the p–i–n diode has been obtained. The ways of optimizing the convertor’s parameters due to improvements in the diode production technology and optimization of the thicknesses of the active emitter layer and i-region of the semiconductor convertor have been indicated.

Emission tomography is a promising method for the diagnostics of thelateral uniformity of plasma components. However, the technological features of microelectronics allow one to use a strictly limited number of views, which adversely affects the quality of the reconstruction. The earlier proposed model of local inhomogeneities (MLI) allows one to resolve the diagnostic difficulties of the lateral homogeneity of the components of low-temperature plasma in the case of the two-view fan-like scanning scheme. In this work, the model is supplemented taking into account an additional factor affecting the accuracy of the tomographic reconstruction, namely, the dependence of the radiation intensity recorded by the optical angular sensor upon the distance to the radiating plasma particle. This was taken into account for the tomographic reconstruction using the method of the maximum entropy, which is basic for MLI.

A typical design flow for a high-performance System-on-Chip usually includes memory compilers, which are implemented by different CAD producers for a given technology. These compilers allow to create automatically all file views for a memory unit using its configuration given by a user. However, there was no memory compiler for a 0.25-micron CMOS SOI process used in some our projects. At the same time, chips we were developing in this process had a wide variety of memories including register files. We developed new design approach and patented a multiported modular bitcell. Additionally, a schematic and layout library of basic cells was created to implement register files with different number of read and write ports. This gave rise to development of design flow and a program, which generates typical file views automatically.