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The electronics world is very well described in two distinct but dependent interdisciplinary areas, namely hardware and software. Arithmetic operations are very vital building blocks of an electronic system. An algorithm is a systematic arrangement that helps develop a sophisticated electronic system, including hardware and software aspects. Addition, subtraction, multiplication, and division are critical elements of arithmetic implementation in the electronic system, but fewer efforts have been made to implement division than other arithmetic operations, even though the number of transistors on a chip is increasing beyond the Moore’s law prediction. It is quite complicated to implement arithmetical operations; here, a sophisticated algorithm is essential to successful implementation. Technological upgrades are leading to a new paradigm of applications, where the performance of a division circuit or block is a vital and critical feature of a successful system. The lexicon of algorithms used in the implementation of the division operation in electronics systems is discussed in detail in the present article, which indicates the mathematical formulation, criticality, conversion pattern, hardware requirements, and logic used for conversion. The current report describes the broad classification of dividers into basic classes named digit recurrence, high radix, functional iteration, estimation, a look-up table, and variable latency. It also illustrates that, in practical implementation, many algorithms have been developed that combine one or many classes and are implemented with different hardware architectures. The study indicated the possibility of improving the presently available algorithms or creating a new algorithm to enhance practical implementation.

The diffusion welding (DW), known as direct bonding technique could be more used as an alternative approach to develop silicon carbide (SiC) Schottky rectifiers to existing mainstream metallization contact technologies. Measured results for p-type 4H-SiC Schottky barrier diodes (SBD) arepresented. And comprehensive numerical study to characterize the device has been performed. The simulations are carried out with ATLAS software (Silvaco). The measured and numerically simulated forward current-voltage (I–V) and capacitance-voltage (C–V) characteristics in a large temperaturerange are analyzed. Some of the measured p-type 4H-SiC Schottky diodes show deviation in specific ranges of their electrical characteristics. This deviation, especially due to excess current, dominates at low voltages (less than 1 V) and temperatures (less than room temperature). To verify the existence of electrically active defects under the Schottky contact, which influences the Schottky barrier height (SBH) and its inhomogeneity, the deep level transient spectroscopy (DLTS) technology was applied. DLTS measurements show the presence of a deep-level defect with activation energy corresponding typically for multilevel trap clusters.

Today, the use of computers is very common and unavoidable almost in every field. The enhancement of the circuit integration process from micrometer scale to nanometer scale escalates the great demand for less costly and reliable embedded solutions. Computer systems, embedded systems, or electronic systems are very generalized in many working sectors like automotive, biomedical, communication, aviation, and transport industries. Thus to perform their work reliably, it is important to have sophisticated arithmetic and logical unit to perform its task intelligently. Many efforts have been made from the beginning to implement addition, subtraction, multiplication, and division type basic arithmetic operations electronically to provide a high computation quality. The division is critical and vital for a sophisticated and reliable computational system among all basic arithmetic operations, but the implementation of the divider is difficult due to its inherent properties. We have to derive division operation in terms of successive subtraction or multiplication formation. Electronic implementation of divider takes multiple clock cycles. A complex number is represented as a vector equivalent of a real number and an imaginary number; thus, we have to perform the same operation twice with more working conditions in complex number arithmetics. This criticality of complex division implementations leads to the use of software-based complex division whenever required, but the demand for complex numbers in various essential engineering application such as earth fault distance protection, acoustics pulse reflectometry, astronomy, non-linear radio frequency measurements, digital signal processing demands for a formulation of sophisticated and efficient operational and implementational algorithms for the complex number representation and computation in the central processing unit of microprocessors or embedded, computer, electronic systems. In this article, we explained the basic stages of complex division by Baudhayan Triplet algorithm using novel state of the art USP-Awadhoot divider. In this article, we explained the workflow of the Baudhayan Triplet algorithm for implementing complex division operations efficiently. The Baudhayan Triplet algorithm provides an area-efficient way of implementing a complex divider.

High-throughput microflow cytometry has become a focal point of research in recent years. In particular, droplet microflow cytometry (DMFC) enables the analysis of cells reacting to different stimuli in chemical isolation due to each droplet acting as an isolated microreactor. Furthermore, at high flow rates, the droplets allow massive parallelization, further increasing the throughput of droplets. However, this novel methodology poses unique challenges related to commonly used fluorometry and fluorescent microscopy techniques. We review the optical sensor technology and light sources applicable to DMFC, as well as analyze the challenges and advantages of each option, primarily focusing on electronics. An analysis of low-cost and/or sufficiently compact systems that can be incorporated into portable devices is also presented.

Single event upset simulation performed for radiation study over the device by studying ionized current generation. In this paper, we are discussing the investigation of n-type SiC-Silicon heterojunction diode. SILVACO ATLAS TCAD is used for realizing its 2D, 3D structure, and performing different simulation-based studies. In this paper, we focused on the Single event upset (SEU) behavior of Silicon Carbide -Silicon heterojunction diode with different internal structures. All simulations performed over the range of -10V to +10V voltage range. 2D, 3D structure built with 10mm by 10mm (10mm) boundary also has gradual doping concentration throughout the device.

Electronic implementation of mathematical operations is very important and critical part of digital system. The major aspects that must be considered are quotient convergence rate, hardware primitives, overheads, and mathematical formulation. Many algorithms were implemented to achieve dividers, which provide inflexible solutions without any percentage of error. In actuality there exist many error-resilient applications where such types of dividers fail to work satisfactorily in terms of power consumption and overall circuit performance. This paper highlights the different estimation or prediction-based dividers. In this paper, we highlighted the key feature points of conversion for approximation and functional iteration class dividers.

The MEMS (Micro-Electro-Mechanical Systems) or NEMS (Nano-Electro-Mechanical Systems) based tensile testing platform serves the purpose of material characterization and failure behaviors at submicron and nanoscopic scales. In the electrostatic transduction of devices, capacitance and electrostatic-forces are the most critical parameters need to be evaluated for the tensile testing setup. In this work, we model a unit cell of a capacitance-based displacement sensor and actuator using the FEM (Finite Element Modeling) tool ANSYS. We study the change in capacitance with respect to transverse and lateral displacements of the capacitor plates and study the relationship between the attractive electrostatic forces generated by applied voltages. Additionally, the influence of fringe fields on the capacitance of unit cell displacement sensors is also studied. Furthermore, the simulation results obtained from FEM ANSYS are compared with the analytical results.

Silicon carbide (SiC) is a wide-bandgap (WBG) semiconductor material with high thermal conductivity and radiation harness that have good potential to develop a new generation of power devices for operating at the higher temperature, high frequency, high power applications. In this paper, various manufacturing process (MP) parameters of diffusion welding (DW) p-type 4H-SiC Schottky contact developments are studied. Deposition temperature and pressure influence the DW Schottky barrier diodes (SBD) electrical characteristics and observed their barrier inhomogeneity. The lower doping concentration in the epilayer improves the Schottky contact characteristics with the same MP parameters. Additionally, Schottky contact with DW deposition technology shows better electrical contact compare to ion-sputtering deposition technique. Furthermore, temperature dependency of forward current-voltage (I–V), capacitance-voltage (C–V), and barrier height correspond to ideality factors measurements of DW two-MP parameters shows that there are higher barrier inhomogeneities at the metal and SiC interface compare to one-MP parameters for Aluminum (Al)-foil/p 4H–SiC SBDs.

In the last decade, silicon carbide (SiC) has gained a remarkable position among wide bandgap semiconductors due to its high temperature, high frequency, and high power electronics applications. SiC heterostructures, based on the most prominent polytypes like 3C-SiC, 4H-SiC and 6H-SiC, exhibit distinctive electrical and physical properties that make them promising candidates for high performance optoelectronic applications. The results of simulations of nn-junction 3C-4H/SiC and 6H-4H/SiC heterostructures, at the nanoscale and microscale, are presented in this paper. Nanoscale devices are simulated with QuantumWise Atomistix Toolkit (ATK) software, and microscale devices are simulated with Silvaco TCAD software. Current-voltage (IV) characteristics of nanoscale and microscale simulated devices are compared and discussed. The effects of non-ideal bonding at the heterojunction interface due to lattice misplacements (axial displacement of bonded wafers) are studied using the ATK simulator. These simulations lay the groundwork for the experiments, which are targeted to produce either a photovoltaic device or a light-emitting diode (working in the ultraviolet or terahertz spectra), by direct bonding of SiC polytypes.

During the last few years graphene has emerged as a potential candidate for electronics and optoelectronics applications due to its several salient features. Graphene is a smart material that responds to any physical change in its surrounding environment. Graphene has a very low intrinsic electronic noise and it can detect even a single gas molecule in its proximity. This property of graphene makes is a suitable and promising candidate to detect a large variety of organic/inorganic chemicals and gases. Typical solid state gas sensors usually requires high operating temperature and they cannot detect very low concentrations of gases efficiently due to intrinsic noise caused by thermal motion of charge carriers at high temperatures. They also have low resolution and stability issues of their constituent materials (such as electrolytes, electrodes, and sensing material itself) in harsh environments. It accelerates the need of development of robust, highly sensitive and efficient gas sensor with low operating temperature. Graphene and its derivatives could be a prospective replacement of these solid-state sensors due to their better electronic attributes for moderate temperature applications. The presence of extremely low intrinsic noise in graphene makes it highly suitable to detect a very low concentration of organic/inorganic compounds (even a single molecule ca be detected with graphene). In this article, we simulated a novel graphene nanoribbon based field effect transistor (FET) and used it to detect propane and butane gases. These are flammable household/industrial gases that must be detected to avoid serious accidents. The effects of atmospheric oxygen and humidity have also been studied by mixing oxygen and water molecules with desired target gases (propane and butane). The change in source-to-drain current of FET in the proximity of the target gases has been used as a detection signal. Our simulated FET device showed a noticeable change in density of states and IV-characteristics in the presence of target gas molecules. Nanoscale simulations of FET based gas sensor have been done in Quantumwise Atomistix Toolkit (ATK). ATK is a commercially available nanoscale semiconductor device simulator that is used to model a large variety of nanoscale devices. Our proposed device can be converted into a physical device to get a low cost and small sized integrated gas sensor.

Algorithm is the way of performing any task in a correct way to reach desired goal. Algorithm is very important factor in any digital world. In digital world, is complicated to implement arithmetical operations. Arithmetic and logical unit stands to be a very vital unit of any embedded or digital processors. Following Moore's Law density of logic units has increased tremendously over couple of decades, which provides enough availability of resources to implement all arithmetic operations. Amongst addition, subtraction, multiplication and division, division is the toughest one to implement digitally. Till date, many different algorithms were developed to provide better result to division implementation in digital hardware. Generally, the major aspects that must be considered are quotient convergence rate, hardware primitives, overheads, and mathematical formulation. Usually division algorithms have five different classes and several types. Many practical dividers are made up of hybrid class concept. In today's high-speed digital life, it is important to implement correct division. This paper is focused on the study of different algorithms to understand how they work, which their limitations are and how it is possible to improve them and the possibility of developing new division algorithms.

Nowadays graphene and its derivatives have gained the interest of researchers due to their exceptional optical, electrical and chemical attributes. They have emerged as potential candidates for electronics and optoelectronics sensor applications. Graphene is highly sensitive to any physical change in its surrounding environment that makes it a suitable candidate for sensing a large variety of organic and inorganic molecules. Volatile and flammable organic compounds like acetone and methane can lead to fatal accidents in domestic and industrial environments. In this article, nanoscale simulations of graphene nano-sheet based methane and acetone detector have been done. Intrinsic 4H-SiC has been used as a substrate for graphene nano-sheet. These simulations have been carried out in QuantumWise Atomistix Toolkit (ATK) software that is an atomic scale semiconductor device simulator. A noticeable change in the density of states (DOS) and electrical conductivity through the device has been observed in the presence of target molecules. This change in electrical conductivity through this nano-scale device can be used as a detection signal for methane and acetone molecules to develop a physical sensor.

Over the last decade graphene based electronic devices have attracted the interest of researchers due to their exceptional chemical, electrical and optical properties. Graphene is very sensitive to any physical changes in its surrounding environment and, inherently, has very low electronic noise. This property of graphene makes it a suitable candidate for sensor applications. The purpose of the work presented in this article is to demonstrate the ability of graphene derivatives to detect toxic organic compounds like phenol and methanol. A novel method for the detection of organic compounds (phenol and methanol) has been introduced in this article. In this method, a change in the photocurrent, as well as electric current, have been used as detection signals to improve the sensor accuracy and selectivity for specific target molecules. A nanoscale electronic device simulator, Quantumwise Atomistix Toolkit (ATK), has been used to simulate graphene nanosheet and armchair graphene nanoribbon based sensors. Devices density of states (DOS), current&ndash, voltage curves and photocurrent curves have been calculated with the ATK simulator. In the proximity of target molecules, a significant change in DOS, electric current and photocurrent have been observed. The simulated graphene based structures can be converted into physical sensors to obtain a low cost, small sized, integrated sensing device.

In the last decades, silicon carbide (SiC) based heterostructures have gained a remarkable place in research field due to their exceptional properties. These properties make SiC highly suitable for high temperature, high frequency, and high power electronics applications. The most prominent polytypes (among 200 types) of SiC like 3C-SiC, 4H-SiC and 6H-SiC, have distinctive electrical and physical attributes that make them promising candidates for high performance optoelectronic applications. Silicon (Si) also has been accepted as a promising material for wide range of electronic, optical and optoelectronic applications. Heterostructures fabricated by the direct bonding of SiC polytype and Si may have interesting physical and electrical attributes. In this paper, micro and nano-scale simulations of the nn-heterostructures of Si/4H-SiC and Si/3C-SiC have been done with Silvaco TCAD and QuantumWise Atomistix Toolkit (ATK) softwares respectively. Voltage-current density characteristics of the nanoscale and microscale simulated devices are computed and discussed. In nanoscale devices, the effects of defects due to lattice misplacements (axial displacement of bonded wafers) are also studied. These simulations are the preparation for our future experiments, which are targeted to produce either a high electron mobility diode or a light emitting diode, by direct bonding (diffusion welding) of SiC polytypes.

Geographically India is having very diverse geometric conditions, which lead to many irrigational conditions and circumstances. As per the survey conducted by the Government of India, 75% of the population lives in the countryside where farming is the key source of earning. Present studies indicate that there is a drastic change in the weather condition due to globalization and scarcity of resources, which have directly affect adversely on the farming. The major issues that raise the rate of reducing farming conditions can be consider as improper irrigation systems, Losses, Improper practices etc. In present irrigation system, farming is very tedious and involves the physical presence of a farmer. Due to improper timings of electric supply for field irrigation system sometimes the conditions were so uncomfortable and dangerous too for watering the field thus looking into those problems faced by farmers we proposed a low cost easily maintainable watering solution for farmers. In this, we use preexisting Mobile GSM network and with the help of Automatic AC Motor Starters, we will control the action of Water irrigation systems. The complete design is based on a simple SEE – SAW Structure of Starter Automation. The focus of this design is to keep design criticality as less as possible, which makes it easy to maintain and repair.

In recent years, graphene has sparked the interest of researchers due to its promising electrical and physical attributes. These attributes make it highly suitable to develop electronic devices with ultra-high mobility of charge carriers. Meanwhile silicon carbide (SiC), a wide bandgap semiconductor material, is being used for high temperature optoelectronic applications. SiC has more than 250 different crystalline forms, these are called polytypes. Some of these polytypes (such as 4H-SiC, 6H-SiC and 3C-SiC) have exceptional physical and electrical properties. Electronic devices which have SiC and graphene as their constituent materials may combine the outstanding attributes of both materials. This article attempts to simulate electronic devices having SiC and graphene as their constituent materials. For this purpose, simulations of a novel nn-heterojunction 4H-6H/SiC diodes with the inclusion of an armchair nanoribbon layer have been carried out. All of the simulations have been run using QuantumWise Atomistix Toolkit (ATK) software, which is an atomic scale electronic device simulator. The density of the states, charge carrier densities and current-voltage curves of the simulated devices have been computed. The simulation results showed a significant improvement in the electrical conduction properties of nn-heterojunction 4H-6H/SiC diodes after the inclusion of the armchair graphene nanoribbons. These simulations provide the groundwork for our future experiments, which will be targeted on fabricating high mobility diodes and/or field effect transistors.

Wide-bandgap (WBG) power semiconductor devices have good potential to replace Silicon-based devices for operating at higher temperatures. Silicon carbide (SiC) currently represents an established WBG candidate for developing power Schottky barrier diodes (SBD) used in power electronics that are required for the next generation power devices. Very few information is available about P-type 4H-SiC substrate being used for realization of SBD. Pre-production Technological computer aided design (TCAD) simulation of SBD, where p-doped epitaxial layer on p-type 4H-SiC substrate corresponds to experimental structures (currently in manufacturing process) could generate defects under the contact. P-type SiC SBD with some defects types is also examined for evaluating the influence on the forward current and reverse voltage blocking. Forward and reverse bias static characteristics are obtained for p-type 4H-SiC SBD at temperatures in the range of 300K to 600K. The currents are shown to have a large on resistance and tunneling component depending on the defects. The SBD device simulation shows that there is significant impact on the reverse current and voltage despite of the very thin defective layer. The reverse breakdown voltages of the diodes were found to decrease from several hundred volts to -100 V indicating the presence of defects edge leakage currents. The structural properties and characteristics of the resulting defects in the schottky contact layer are discussed.

Over the last decade graphene and its derivatives have stimulated the interest of researchers due to their extraordinary electrical, optical and chemical properties. Graphene has emerged as a potential candidate for electronic sensors and optical sensors applications. The purpose of the work presented in this article is to contribute in this novel field by simulating graphene nano-sheet based sensor to detect phenol and methanol molecules. QuantumWise Atomistix Toolkit (ATK) software has been used to carry out the sensor simulations. A significant change in the density of states and conductivity of the graphene have been noticed in the proximity of the target molecules. This change in the conductivity of graphene nano-sheet has been used as a detection signal. These simulations lay the groundwork for our physical experiments, which are targeted to produce a cheap sensor.

Impedance spectroscopy is a common approach in assessing passive electrical properties of biological matter. However, several problems appear in microfluidic devices in connection with high sensitivity signal acquisition from small volume sensors. The developed compact analyzer provides fast impedance spectroscopy measurement from three sensors in direct and differential modes. Measurement deficiencies are minimized with optimized electronics, measurement method, signal processing and mechanical design of the analyzer. Proposed solutions are targeted to the creation of reliable point-of-care (POC) diagnostic and monitoring appliances including lab-on-a-chip type devices in next steps.

This work aims to understand the thermo-electromechanical behaviour of a silicon-based, chevron type thermal actuator (TA) in microelectromechanical systems (MEMS). The analysis presents simple analytical and numerical models of the chevron type thermal actuator (CTA). The analytical models are compared with the results of finite element models (FEM) to optimise the TA design parameters and validate thermo-electromechanical analysis. Moreover, analytical models for deflection allow for a much easier optimisation and more straightforward design process than with the finite element approach. Since the deflection of chevron thermal actuators depends on many variables, design guidelines are introduced to create an optimum, efficient chevron thermal actuator for the desired deflection under a specified external load. This study shows that the CT A-optimised beam length is 2000 $\mu \mathrm{m}$ and optimised inclination is 5°. Chevron type TA deflection will be 50% less for higher inclination angles greater than those between 5°-10°. The minimum voltage required for the displacement of 3.5 $\mu \mathrm{m}$ is 3.3 V and a power consumption of approximately 3 mW was obtained from this study. This optimised design and thermo-electromechanical analysis can be used to design and investigate the high switching response in a silicon-based chevron type TA.

Silicon substance (is also known as Quartz) is an abundant in nature and the electrical properties it exhibits, plays a vital role in developing its usage in the field of semiconductor. More than decades we can say that Silicon has shown desirable signs but at the later parts it has shown some research potential for development of alternative material as semiconductor devices. This need has come to light as we started scaling down in size of the Silicon material and up in speed. This semiconductor material started exhibiting several fundamental physical limits that include the minimum gate oxide thickness and the maximum saturation velocity of carriers which determines the operation frequency. Though the alternative semiconductors provide some answers (such as III-V’s for high speed devices) for a path to skirt these problems, there also may be some ways to extend the life of silicon itself. Two paths are used as for alternative semiconductors i.e alternative gate dielectrics and silicon-based heterostructures. The SiC material has some strength properties under different conditions and find out the defects available in the material.Silicon substance (is also known as Quartz) is an abundant in nature and the electrical properties it exhibits, plays a vital role in developing its usage in the field of semiconductor. More than decades we can say that Silicon has shown desirable signs but at the later parts it has shown some research potential for development of alternative material as semiconductor devices. This need has come to light as we started scaling down in size of the Silicon material and up in speed. This semiconductor material started exhibiting several fundamental physical limits that include the minimum gate oxide thickness and the maximum saturation velocity of carriers which determines the operation frequency. Though the alternative semiconductors provide some answers (such as III-V’s for high speed devices) for a path to skirt these problems, there also may be some ways to extend the life of silicon itself. Two paths are used as for alternative semiconductors i.e alternative gate dielectrics and silicon-based heterostruc...

Power semiconductor devices are facing different failure mechanisms which limit the safe operating area of these devices. Two different mechanisms influence the thermal behaviour of power devices, first the ambient temperature, and secondly self-heating phenomenon described traditionally over the lattice thermal behaviour model. It is demonstrated in different published materials how the device internal processes can be investigated by means of device numerical simulation procedure. In our paper we focus on the numerical analysis of GaAs based power pin structures applied for detection of anomalies in the switching process of devices taking into account the influence of ambient temperature amplified by the self-heating phenomenon introduced over the lattice thermal model. Due to the fact that the switch-off of power diode structures is one of most critical acts in different power converters, like for example DC/DC converters, we put our focus on the exact thermal description of the devices under the switching process. Special effort has been taken for the situations, where during the switching process the total thermal situation leads the device close to the thermal breakdown instead of normal electrical breakdown. The influence of current crowding plasma generation near the metallic contacts seems to take place. The smooth snappy switching characteristics behaviour and it’s mechanism under the temperature influence is simulated and the results are presented. Examples on current destabilizing effects in the switching process and the limitations of switching current detected from the device simulation are discussed.

In this paper the reverse recovery of a fast GaAs pin-diode is investigated. Simulations show that the snappy behaviour observed at the measurements of the reverse recovery process of the experimental diode could take place only in cases where significant inductance in the measurement circuit is involved. Deep traps are not the cause for the snappiness effect.

The Thomas Johann Seebeck Department of Electronics at the Tallinn University of Technology has studied the properties of Schottky contacts since the 1980s. The theoretical studies have been accompanied by analytical and numerical computer simulations. Realisation of SiC complementary power Schottky diodes has been possible since 1994, using diffusion welding (DW) metallisation technology. Measurement of the electrical properties of the produced samples offers excellent possibility to verify and enhance computer models, and as feedback provides possible explanations to phenomenon found in the measurement results. This paper provides a comparison between measured and simulated results for SiC Schottky power diode structures. The paper addresses the simulation results investigating the influence of deep energy traps and/or defects on electrical characteristics of SiC Schottky diodes manufactured using DW metallisation technology. The numerical model includes the exact model for describing the behaviour of deep energy traps in the epitaxial layer. The analysis takes into account the influence of ambient temperature on static characteristics of the device. The outcome of this particular research is addressed for the optimisation of the switching devices applied in the power converters, with the aim of reducing the general energy consumption in different power grids.

The PBT is a short channel device and hot electron effects are expected to be important and the transport model used in the simulation is critical. The present work compares the effect of different transport models on the operation of a submicron PBT. The transport model used are the ordinary drift-diffusion model and the hydrodynamicc models as they are implemented in MEDICI Ver. 1.1. In submicron devices the transport parameters become both device and bias dependent. The transport parameters are directly related to the distribution function and should be extracted from the solution of Boltzmann's Transport Equation (BTE). The most popular and effective way of solving the BTE is Monte Carlo simulation. In this work we have extracted transport parameters from Monte Carlo simulation using one dimensional boundary for particles and a fixed electric field extracted from two-dimensional simulation in MEDICI. The Monte Carlo simulation, parameter extraction and MEDICI simulation have been repeated until the change in electric field between iterations could be neglected. Both I-V and fT results have been analysed. It is clear that the hydrodynamic model gives higher current levels and higher fT than the drift-diffusion model.

The paper gives short overview of SiC based complementary multi guard ring JSB structures and the numerical model to be used in the analysis. The static U-I characteristics are under investigation. The geometry and temperature influence has been analyzed.

A new generalized analytical model has been developed for analysing SiC polytypic heterojunctions. The forward and reverse biasing situations have been investigated and two novel results have been detected. First, the activation energy plays a major role in the determination of the place of the so-called knee point. The smaller the activation energy, the lower value has the knee point. Similar behaviour has been observed also by the increase of the temperature. Second, the density of traps and their temperature behaviour limits the current approximately at 350 °C, which means that the increase of the reverse current and therefore the reverse biasing is not in correlation anymore.

During the last decade, silicon carbide (SiC) and its heterostructures with other semiconductors have gained a significant importance for wide range of electronics applications. These structures are highly suitable for high frequency and high power applications in extremely high temperature environments. SiC exists in more than 200 different polycrystalline forms, called polytypes. Among these 200 types, the most prominent polytypes with exceptional physical and electrical attributes are 3C-SiC, 4H-SiC and 6H-SiC. Heterostructures of these SiC polytypes with other conventional semiconductors (like Si, Ge) can give rise to interesting electronic characteristics. In this article, Germanium (Ge) has been used to make heterostructures with 3C-SiC and 4H-SiC using a novel technique called diffusion welding. Microscale and nanoscale simulations of nn-heterojunction of Ge/3C-SiC and Ge/4H-SiC have been done. Microscale devices have been simulated with a commercially available semiconductor device simulator tool called Silvaco TCAD. Whereas nanoscale devices have been simulated with QuantumWise Atomistix Toolkit (ATK) software package. Current-voltage (IV) curves of all simulated devices have been calculated and compared. In nanoscale device, the effects of defects on IV-characteristics due to non-ideal bonding (lattice misplacement) at heterojunction interface have been analyzed. Our simulation results reveal that the proposed heterostructure devices with diffusion welding of wafers are theoretically possible. These simulations are the preparations of our near future physical experiments targeted to fabricate SiC based heterostructure devices using diffusion bonding technique.