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Thermal oxidation at various temperatures on magnetron sputtered hafnium films shown significant effect on stoichiometry, crystallographic structure and electrical and optical properties. X-ray photoelectron spectroscopy confirms the stoichiometry of HfO2 films by showing the relevant shift in the core level binding energies of hafnium and oxygen after increasing the oxidation temperature to 600 °C. The EDAX analysis also confirmed the required composition of HfO2 films. The presence of monoclinic HfO2 structure was identified by XRD for the films oxidized at 600 °C. The interface quality at HfO2/Si stacks was improved as a function of oxidation temperature. The optical band gap and the refractive index of the HfO2 films increased with increase of oxidation temperature.

In the present work, glasses of a particular composition (60-x) P 2 O 5 -20CaO-17Na 2 O-3K 2 O: xSrO (0.5≤x≤1.5) mol% were synthesized using conventional melt quenching technique. Further, samples were characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Differential Thermal Analyses (DTA) techniques and Fourier Transform Infrared (FT-IR) spectra. In vitro bioactivity was evaluated by soaking glass ceramic powders in SBF solution for 7 and 15 days. XRD patterns of glass ceramics have clearly confirmed the formation of various crystalline phases K 2 Sr(PO 3 ) 4 , α-Ca 2 P 2 O 7 , Ca 2 Sr(PO 4 ) 2 , Ca 5 (PO 4 ) 3 (OH) and Ca 3 (PO 4 ) 2 . Random spreading of uneven sized micro crystals with distinct boundaries in the glass matrix have been observed from SEM pictures. DTA scans revealed an increase in the content of SrO with heating rate causes the glass transition (T g ) and crystallization temperatures (T c ) towards lower side, that confirms the decrease in rigidity of glass network. FT-IR spectra showed that there is an increase in the degree of structural disorder and the formation of a crystalline hydroxyapatite layer with soaking time. From the analyses of all the above results, it can be concluded that the sample doped with 1.5 mol% of strontium is found to exhibit high bioactivity.

Objectives: To design a simple piezoresistive cantilever punched with different shaped objects in the concept of Stress Concentrated Region (SCR) and study the effects of geometrical changes, addition of materials and applied loads to find out optimum conditions resulting high displacement sensitivity. Methods/Analysis: Design and simulation of piezoresistive cantilever with different punched objects (Circle, Triangle, Rectangle and T-Shape) to explore the maximum deformation. These design attempts indicate the bending of a cantilever under an applied load and solves the deformation of the beam under an applied force. The study also extended to analyze the sensitivity with the change of piezoresistive materials for same applied input force and given geometry. Findings: From the analyses of both the efforts, it is observed that the SiO2 based MEMS piezoresistive cantilever found to exhibit high deformation in turn sensitivity. The reasons for improvement in the sensitivity were discussed in detail by means of dimensional modifications, applied loads and materialistic properties. The design and simulations of a piezoresistive cantilever were carried out using commercial MEMS software tool COMSOL v 5.2a. Novelty/Improvement: This type of study would be useful to detect very minute biological mass changes that enable to overcome low resolution of the read out system for piezoresistive approach. The study of deformation of piezoresistive cantilever under surface stress loading may be treated as loading condition that take place in biochemical sensors.

Background/Objective: Now a day’s electronics industry people are concentrating on low power designs. The growing market of portable electronic systems demands microelectronic circuit with ultra low power dissipation. Method: The accomplished operations in this design are logical operations, the arithmetic operations, and branch operations. The outcome values of these operations stored in the registers and they can retrieve from the same when needed. The low power RISC processor with unbiased double precision FPU is designed without any complication, because the power reduction can do in front end technique. Findings: On MAX V CPLD a low power pipelined 64-bit RISC processor is implemented. Arithmetic operations, logical and branch functions of RISC processor are successfully verified with this design. In order to avoid any misbehavior in the jump instructions, the data will flush in the pipeline automatically by the processor architecture. This processor contains FPU unit, which supports double precision IEEE-754 format operations very accurately. Modelsim software is used to verify the simulation results of the design. The ALU operations and double precision floating point arithmetic operation results will be displayed on 7-Segments.

This article represents the implementation of low power pipelined 64-bit RISC processor on Altera MAXV CPLD device. The design is verified for arithmetic operations of both fixed and floating point numbers, branch and logical function of RISC processor. For all the jump instruction, the processor architecture will automatically flush the data in the pipeline, so as to avoid any misbehavior. This processor contains FPU unit, which supports double precision IEEE-754 format operations very accurately. The simulation results have been verified by using ModelSim software. The ALU operations and double precision floating point arithmetic operation results are displayed on 7-Segments. The necessary code is written in Verilog HDL. Full Text: PDF