Search

Silicon is a nonlinear material and optics based on silicon makes use of these nonlinearities to realize various functionalities required for on-chip communications. This article describes foundations of these nonlinearities in silicon at length. Particularly, self phase modulation and cross phase modulation in the context of integrated on-board and on-chip communications are presented. Important published results and principles of working of these nonlinearities are presented in considerable detail for non-expert readers.

This work is on the design of a fully integrated 0.13-µm CMOS multi-standard power constrained simultaneous noise and input matching low-noise amplifier (PCSNIM LNA). The multi-standard capability is obtained via the implementation of CMOS switches. The input and output matching are fully implemented on a chip, which is uncommon when compared to the existing multi-standard LNA topologies. The multi-standard LNA is operated at 0.9, 1.8, and 2.1 GHz frequencies. The design covered wireless standards of GSM900, DCS1800, and W-CDMA applications. The multi-standard LNA can obtain noise figure as low as 1.72 dB. The third-order intercept point, IIP3, is as high as −4 dBm, while IP1dB is −10 dBm. The power consumption of the design is only 7.4 mW. This resistorless multi-standard LNA design is not just able to operate at three different frequencies but also has a comparable performance with the rest. Its merits are contributed by high linearity and low power.

Since the 1940s, infrared (IR) detection and imaging at wavelengths in the two atmospheric windows of 3 to 5 and 8 to 14 μm has been extensively researched. Through several generations, these detectors have undergone considerable developments and have found use in various applications in different fields including military, space science, medicine and engineering. For the most recently proposed generation, these detectors are required to achieve high-speed detection with spectral and polarization selectivity while operating at room temperature. Antenna coupled IR detectors appear to be the most promising candidate to achieve these requirements and has received substantial attention from research in recent years. This paper sets out to present a review of the antenna coupled IR detector family, to explore the main concepts behind the detectors as well as outline their critical and challenging design considerations. In this context, the design of both elements, the antenna and the sensor, will be presented individually followed by the challenging techniques in the impedance matching between both elements. Some hands-on fabrication techniques will then be explored. Finally, a discussion on the coupled IR detector is presented with the aim of providing some useful insights into promising future work.

This paper emphasis on state-of-the-art of the earlier until the current trend and demand, principles, design considerations, key performance and fabrication technology of RF MEMS switch devices developed over the past few years. RF MEMS switch performance and features such as actuation voltage, insertion loss, isolation and ease with cost of fabrication and applications are compared and discussed.

The performance of a thermoelectric power generator for powering wireless sensor node has been studied and evaluated. This study covers the results obtained from two configurations of thermoelectric cell with heat source temperatures range from 40 to 230 °C. It was found that the highest output voltage is 9.08 V belong to configuration B with two parallel thermoelectric cells. This configuration was capable to power up sensor node compared to configuration A with the lowest heat source temperature at about 200 °C. To enhance the capability of the configurations, DC boost converter circuit has been developed and tested. By connecting to the DC boost converter, configuration A can power up the wireless sensor node with heat source temperature at about 220 °C while the minimum heat source temperature for configuration B was reduced from 200 to 170 °C. This study identified the optimum operation condition to power up wireless sensor node by thermoelectric power generator for remote application and make conclusion as to how to increase the performance of thermoelectric power generator by introducing DC boost converter.

An artificial hair cell sensor is the current technology based on a biological inspiration and is widely used in underwater applications including the glider, robotic and autonomous surface vehicle. These papers discuss a few strategies in relation to the principles of sensing, fabrication, performance, and preliminary measurement data. The MEMS flow sensor is generally needed to replace existing commercial sensors that are inadequate for some applications. Material also provides some advantages to the hair cell sensor. Some materials such as Polydimethylsilaxone and Polyurethane have been investigated. The sensing element is reviewed including the doped piezoresistors, strain gauge and force sensitive resistors. Performance and result of each design will be presented briefly. Finally, the importance and the need for modeling, simulation and experiments will be reviewed based on the latest achievements on that particular research area.

In the current paper, an improvement of piecewise curvature-corrected CMOS bandgap reference (BGR) circuit is proposed. The circuit utilizes piecewise nonlinear curvature-corrected current (PNCCC) in a conventional BGR with a current control circuit, which compensates for the voltage reference at a higher temperature range. The current control circuit (CCC) is used to reduce the total current at low temperature when the PNCCC generator is inactive. The proposed circuit is realized in CMOS 0.13µm and has been verified to be able to save power consumption by 18.6% compared with a circuit without the current control circuit.

The simplicity associated with the piezoelectric micro-generators makes it very attractive for MEMS applications, especially for remote systems. In this paper we reviewed the work carried out by researchers during the last three years. The improvements in experimental results obtained in the vibration-based MEMS piezoelectric energy harvesters show very good scope for MEMS piezoelectric harvesters in the field of power MEMS in the near future.

Frequency hopping spread spectrum with noncoherent M-ary frequency shift keying system is considered. In this study Reed Solomon codes RS (255, 223) are employed in a standard error correction role to provide some Anti-Jamming (AJ) capability with 8-bit symbols. Noise has been added to RS encoded data, which is demodulated at RS decoder perfectly. Matlab simulations have been implemented for numerical results. Graphical results have been plotted between the probability of an erasure versus ρ using RS (255, 223) code for 1 and 2 kHz frequencies. The simulation results have proved that system having RS (255, 223) code with M = 32 require substantially less signal to jammer power ratio to achieve the same bit error probability.

The fluidic based multidirectional flow sensor inspired from artificial cupula was presented in this paper. It is consists of dome-shaped membrane, microchannel and one-side electrode with implementation of electrical double layer capacitor as a sensing element. The PDMS with ratio 20:1 was selected as a material because it is suitable to be implemented as a membrane. The micro-stamping technique for fabrication of dome-shaped membrane was proposed where the uniform thickness of membrane can be achieved. The operating frequency of the sensor using methanol was 1.5 kHz. The flow measurement was done by using water channel which flow rate 10 to 40 cm/s was applied with the resolution of 5 cm/s. The directionality tests for flow direction and angle also were carried out and it is proved that the sensor was able to detect the flow in omnidirectional directions.

This paper presents two novel designs for narrowband tunable low-noise amplifier implementation operating at two frequency standards of 850 MHz and 1900 MHz (cellular frequencies such as GSM, CDMA and DCS standards). Both designs benefits from a simple cascode topology with tunable input and output matching networks. Two novel methods to tune the input resonating frequency are introduced: (1) switched transistor width technique, and (2) switched extra Miller and gate-source capacitances technique. Each technique shows its own pros and cons. A comparison between the post-layout simulations results of two designs is made while they are fully matched in desired frequencies. This paper also gives a comparison table between these designs and other similar works in terms of RF performance. The 0.13-μm RF CMOS tunable LNAs have a minimum and maximum power dissipations of 2 and 4 mW, respectively, depending on the tuned resonating frequency.

This paper presents a fully integrated two-stage narrow-band low noise amplifier which optimized to work in 2.45 GHz center frequency. The topology of inductive source degenerated cascode based on power-constrained simultaneous noise and input matching (PCSNIM) technique has been adopted to make the LNA suitable for low power applications based on 0.13µm Silterra CMOS technology. Post layout simulation results show power gain of 22 dB, NF of 2.06 dB, S11 of −19 dB and S22 of −12 dB while consuming the DC current of 4 mA at supply voltage of 1.2V.

This paper presents a dual-stage LNA design which is enhanced for gain, linearity and noise figure under a certain power constraint. The LNA benefits from an inductively-degenerated cascode amplifier in the first stage which is followed by a common-source amplifier as the second stage. Two techniques are used to improve the linearity of this 24-dB gain LNA while maintaining the noise figure equal to 2 dB. An input 1-dB gain compression point of −21 dBm was achieved at 2.45-GHz operating frequency. The 0.13-µm CMOS LNA draws a 4-mA current from a 1.2-volt power supply.

The application of wireless sensor network for process monitoring of laser cutting process is a promising solution to address the problems in achieving good cutting performance. Wireless sensor network provide real time data monitoring flexibility, maintenance convenient, and easy to relocation for laser cutting process application. This paper presents the development of wireless sensor network for monitoring temperature at cutting surfaces during laser cutting process. The system consists of thermocouple sensors, microcontroller programmable system on chip platform, wireless radio frequency and software data logger. The workability and performance of the system was tested by using gas cutting.

The wireless sensor network market is growing quickly yet is limited by existing short lifetime batteries. Providing a green, virtually infinite alternative power source to traditional energy sources will significantly expand applications for WSNs and other technologies, the use of piezoelectric materials to capitalize on the ambient vibrations surrounding a system is one method that has seen a dramatic rise in use for power harvesting. The simplicity associated with the piezoelectric micro-generators makes it very attractive for MEMS applications, in which mechanical vibrations are harvested and converted to electric energy, these micro generators were designed as an alternative to a battery-based solution especially for remote systems. In this paper we reviewed the work carried out by researchers during the last few years. The improvements in experimental results obtained in the vibration based MEMS piezoelectric energy harvesters show very good scope for MEMS piezoelectric harvesters in the fields of power MEMS and Green Technology in the near future.

The wireless sensor network market is growing quickly yet is limited by existing short lifetime batteries. Providing a green, virtually infinite alternative power source to traditional energy sources will significantly expand applications for WSNs and other technologies, the use of piezoelectric materials to capitalize on the ambient vibrations surrounding a system is one method that has seen a dramatic rise in use for power harvesting. The simplicity associated with the piezoelectric micro-generators makes it very attractive for Micro Electro Mechanical Systems (MEMS) applications, in which mechanical vibrations are harvested and converted to electric energy, these micro-generators were designed as an alternative to a battery-based solution especially for remote systems. In this paper we proposed a design and simulation of MEMS-based energy harvested by using ANSYS11 and COVENTORWARE2008 approaches. The improvements in experimental results obtained in the vibration based MEMS piezoelectric energy harvesters show very good scope for MEMS piezoelectric harvesters in the fields of power MEMS and Green Technology in the near future.

This paper proposed the design of a switchable dual-band low-noise amplifier (LNA) using Silterra 0.18-μm CMOS technology fabrication process. The LNA utilized the single-ended type with cascode inductively source degeneration topology. This topology is best for simultaneous noise and input matching besides capable of reducing the Miller effect as well as improving on the reverse isolation performance. The switchable dual-band LNA can be tuned to center frequency of either 1.575 GHz for global positioning system (GPS) or 2.4 GHz for WLAN 802.11b standard applications. The LNA can cater frequency range of 1.33 to 2.10 GHz and 1.69 to 2.64 GHz for GPS and WLAN application, respectively. The switching of the operating frequency can be achieved by capacitor selection using MOS as switches at its input and output matching network. NMOS switches were implemented as they have lower on resistance and can provide larger gain when compared with PMOS. The selection of the switches is based on the voltage supplied to each switch. The supply voltage for the LNA is 1.8 V and the voltage required to enable the MOS switches is 3 V. Pre-layout simulation for input third-order intercept points (IIP3) are +1.62 dBm and +1.17 dBm for center frequency of 1.575 GHz and 2.4 GHz, respectively. Post layout simulation shows input reflection coefficients (S 11 ) of −15 dB and −16 dB, reverse isolation coefficients (S 12 ) of −56 dB and −50 dB, power gains (S 21 ) of 10 dB and 11 dB, output reflection coefficients (S 22 ) of −13 dB and −15 dB and noise figure (NF) of 3.2 dB and 3 dB for center frequency of 1.575 GHz and 2.4 GHz, respectively. Thus, the design is able to meet the requirements of the desired standards. The LNA consumes current of 18.5 mA at both 1.575 GHz and 2.4 GHz frequencies and therefore resulting a power consumption of 33.23 mW.

The design and simulation of an MEMS-based capacitive bending strain sensor using silicone dope as a plate is presented in this paper. The objective is to design and simulate the performance of a strain sensor using a dielectric material between capacitive plates. The silicone dioxide (SiO 2 ) and polydimethylsiloxane (PDMS) was utilized as the dielectric layer in this model. Several dimensions of the sensor and the dielectric materials were studied as silicon dioxide was also used to increase the performance of the sensor. The application of the sensor is for the spinal fusion monitoring system. The finite element analysis (FEA) was performed using MEMS CoventorWare 2008, and the results were verified using the analytical method. Based on simulation results, the presences of the dielectric material has increased the capacitance output of the sensors and produced greater sensitivity. The sensitivity of the sensor is 24.9–44.48% higher compared with existing sensors. The nominal capacitance of the sensor also improved significantly from 94.16pF to 156.14pF. The sensor also exhibits greater sensitivity at the early stage of the bending strain; the sensitivity of the sensor is up to 0.525pF/μe.

The micro power generation using vibration energy sources appears to be attractive due to its applicability on many situations and environmental conditions. The electrostatic energy harvester has various advantageous over piezoelectric and electromagnetic systems such as reduction in fabrication process complexity and cost, feasibility on MEMS and IC integration, improves the possibility level of integration with silicon based microelectronics and produce voltage within the usable range which can obviating the need of large and expensive generator. This paper presents the design and simulation of SOI-MEMS electrostatic vibration energy harvester using the architect module in CoventorWare2010. Simulation results shows that the newly proposed electrostatic energy harvesting system can produce maximum output power of 5.891µW when the excitation frequency is 2 kHz.

This chapter presents an adaptive Multicarrier Frequency Hopping Spread Spectrum (MCFH-SS) system employing proposed Quasi Cyclic Low Density Parity Check (QC-LDPC) codes instead of the conventional LDPC codes. A new technique for constructing the QC-LDPC codes based on row division method is proposed. The new codes offer more flexibility in terms of girth, code rates and codeword length. Moreover, a new scheme for channel prediction in MCFH-SS system is also proposed. The technique adaptively estimates the channel conditions and eliminates the need for the system to transmit a request message prior to transmitting the packet data. The proposed adaptive MCFH-SS system uses PN sequences to spread out frequency spectrum, reduce the power spectral density and minimize the jammer effects.

Fiber optic sensors are being extensively developed and utilized in various fields, compared to conventional sensing technologies, due to their exclusive properties, such as complete immunity to electromagnetic interference, capability of functioning in hostile surroundings, elevated sensitivity and user-friendliness. The unique characteristics of fiber optic sensors can provide more accurate and precise detection of crack damage in concrete structures, the deterioration of which is one of the major growing problems worldwide. This paper provides a comprehensive critical review and comparison of various approaches used in detecting crack damage using fiber optic sensors. A separate section is devoted to highlight the areas where further improvements are required. The compatibility and sustainability of the latest fiber optic sensors in detecting concrete damage are also studied and evaluated in this paper.

The wireless sensor network (WSN) market is growing quickly yet is limited by existing short lifetime batteries. Providing a green, virtually infinite alternative power source to traditional energy sources will significantly expand applications for WSNs and other technologies, the use of piezoelectric materials to capitalize on the ambient vibrations surrounding a system is one method that has seen a dramatic rise in use for power harvesting. The simplicity associated with the piezoelectric micro-generators makes it very attractive for MEMS applications, in which mechanical vibrations are harvested and converted to electric energy, these micro-generators were designed as an alternative to a battery-based solution especially for remote systems. In this paper we reviewed the work carried out by researchers during the last two years. The improvements in experimental results obtained in the vibration based MEMS piezoelectric energy harvesters show very good scope for MEMS piezoelectric harvesters in the fields of power MEMS and Green Technology in the near future.

This work presents a new scheme for channel prediction in multicarrier frequency hopping spread spectrum (MCFH-SS) system. The technique adaptively estimates the channel conditions and eliminates the need for the system to transmit a request message prior to transmit the packet data. The new adaptive MCFH-SS system employs the Quasi-Cyclic low density parity check (QC-LDPC) codes instead of the regular conventional LDPC codes. In this work performance of the proposed MCFH-SS system with adaptive channel prediction scheme is compared with the fast frequency hopping spread spectrum (FFH-SS) system. The proposed system has full control of that spectrum; it plans for the system to keep off unacceptable adjacent channel interference. When an interferer suddenly changes its carrier, the set of appropriate channels has a large return and resultantly the adjacent channel interference between the systems is reduced. It has been shown from results that the signal power in FFH system exceeds the average by at least 6.54 dB while in the proposed MCFH-SS system signal power exceeds the average only 0.84 dB for 1% (correct use) of the time. The proposed MCFH-SS system is more robust to narrow band interference and multipath fading than the FFH-SS system, because such system requires more perfect autocorrelation function.

A simple fabrication method on wet etching and thermal evaporator had been used to fabricate microfluidic three gold (Au) electrodes assembled with polydimethylsiloxane (PDMS) was reported in the present work. In this work, we studied the suitable size of electrode area that can fulfill the Randle-Sevcik equation for reversible redox process. The voltammograms of 0.01 M K 3 Fe(CN) 6 in 0.1M KCl at 1.04 mm2 electrode area demonstrates the current peak ratio of unity thus suitable to be further developed as a three electrode sensory system with Ag/AgCl reference electrode. The plotted graph for peak current vs electrode area satisfied the Randle-Sevcik equation as well. Cyclic Voltammetry (CV) analysis proved that the fabricated sensor was reliable in the range of 24 hours at the room temperature of 25°C.

In this paper, we proposed a sealing technique for a sealing glass cap with a ceramic substrate by using silica coating liquid to increase the performance of fluid-based inclination sensor in heat-resisting and durability characteristic. The sensor was developed with one-side-electrode-type structure and propylene carbonate was used as electrolyte. The sensor uses capacitance change to detect the angle of inclination, and it is capable measuring inclination at supply voltage 1.5 V. The diameter of glass cap and height were 4.0 mm and 2.0 mm, respectively. The linearity of characteristic can be improved when the supply voltage was set at 1.5 V. The sensitivity, response time and resolution of sensor were 4 mV/deg, 0.6 s and 1.8 deg, respectively at the supply voltage 1.5 V. The temperature characteristic was evaluated between −10 °C to 50 °C.

DOE (design of experiment) with simulation approach is presented that allow early visibility, guidance, and analysis of clamp placement in early design stage (power template design) on a chip level complexity. ESD robustness of product is largely attributed to the degree of correct implementation of ESD design rules in a highly complex design. Correct clamp placements is one of the most difficult and less guidance. Therefore, a 'reliable' & 'comprehensive' ESD clamp placement analysis is urgently needed. This simulation would deliver a preliminary guidance of clamp placement. It provides the information of where the most probable clamp placement is in the particular power template design. Since it takes into consideration the ESD ohm rules requirements during the construction of ohm sector, it would have a very high confident level that the design would not encounter much issue in the ESD resistance checkout later. Apart from the ESD design rules checkout, we also couple with TLP (transient line pulse) testing which has proven this approach could deliver a promising ESD protection robustness. We can characterize, co-relate, and compare our simulation with the Si data from various design perspectives. All in all, the real strength of this simulation is the ability to provide earlier design guidance & optimization options starting from the product concept phase (power template design stage), which allows to align ESD with all design issues on a cost and time efficient way. Without the simulation, designer would need to manually calculate the resistance , rely on past experience and some assumption with nil data support which is tedious & error prone for complex design nowadays. This allows ESD design rules compliance in the early design stage, thus enhancing the approach of "correct-by-construction" on ESD design.

In this paper, we proposed a new physical-based equation to model the CMOS transistor STI y-stress (in the direction of channel width). It can be used in any SPICE MOS model and it has been verified on 0.13 um CMOS transistors. The physical characteristics of the compressive STI y-stress effect on saturation drain current, Idsat are captured by using a new proposed transistor layout method. The equation that is able to describe the physical characteristics of the STI y-stress effect is incorporated into the electron and hole mobility, uO of the SPICE model to capture the y-stress effect on Idsat. With the combination of the new y-stress parameters and the default delta width parameters in the SPICE model, we are able to fit the simulation curve to the hook shaped Idsat curve from the actual silicon data.

In this paper we analyzed the mismatch characteristics of poly resistors. We found that the P+ poly resistor mismatch characteristics do not follow the linear inverse square root dependence. Instead, the P+ poly resistor mismatch follows the quadratic of inverse square root (or a simple inverse area) dependence. N+ poly resistor mismatch, however does obey the expected standard inverse square root dependence.

In this paper an integrated system is developed to detect shock vibration by using MEMS accelerometer. The interface circuit which converts the signal from an accelerometer capacitive element to a pulse signal for digital signal processing is built. Changes in the capacitance between fixed and movable plates are induced by acceleration from shock vibration. Interface circuit incorporating this capacitor then extracts the acceleration signal and converts it to digital or analog form using microcontroller microprocessor. GUI is developed to make the integration data system more interesting and user friendly. The sensing of MEMS and monitoring software are integrated together to provide real time acquire data and graphical visualization for monitoring, recording and analysis purposes.

This paper deals with the theory, fabrication and test results of an ultrasonic technique which is used to measure vacuum in a container. Ultrasonic transmitter and receiver, working at 40 KHz, are used for conducting the experiments. The sensitivity of measurement is a function of applied voltage to the transmitter. Results on a prototype model are included and relationship between output voltage and pressure is appreciably linear.

Mechanical compressive stress induced by shallow trench isolation (STI) and transistor mismatch is the two important effects that we should take into account when scaling down CMOS transistors. In this paper, we study the relationship between these two effects. Our finding shows that STI induced stress effect improve NMOS Id matching but degrade PMOS Id matching. These effects become more obvious for small size transistors. The STI stress effect has no significant effect on V/sub t/ mismatch.

This work studied the flow behaviour of microfluidic-based acoustic sensor at a region where the flow of fluid was considered to be significant in determining the overall flow behaviour of the system flow in microchannel. The study was carried out based on finite element model (FEM) using ANSYS multiphysics package. Two structural parameters, reservoir or chamber height and the number of microchannel were used as the varying parameter. The flow behaviour was then analysed based on pressure distribution, velocity contour and velocity vector for a single and dual microchannel configuration with different reservoir height. The height was varied in the range of 20 to 100 μm due to limitation in the thickness of mold material during fabrication. Simulation results reveal that the flow response was not critically affected by the chamber height, whereas the dual microchannel configuration had an approximately a factor of 2.8 higher in terms of its flow velocity compared to the single microchannel configuration. This effect was referred as an amplification factor of the flow response due to this structure variation.