Electronic Devices and Semiconductor Manufacturing Commons^™

Spice Modeling Of Biosensing Field-Effect Transistor, Alex Castro

Electrical Engineering

This project created a user manual on how to generate an easily configurable and implementable Spice model for Field Effect Transistor (FET) devices created in the Cal Poly clean room. The document contained step by step procedures depicting the proper execution techniques and example results for different experiments required to gather the proper information for these models. This testing methodology was shown for finding the numerous different device parameters of a FET, including the I-V curves, threshold voltage, and subthreshold current values. The manual then described how to transfer this data into a new Spice model to allow for simulation …

Potassium And Sodium Sensing Isfet Device And Array, Liam Stephen Hayes

Electrical Engineering

The use of Ion-Sensitive Field Effect Transistors (ISFETs) as a means of testing a person’s potassium concentration in real-time has broad applications in the consumer space. An avid runner could use such a device to keep track of their hydration and salt levels. A hospital could use it for patients who require around-the-clock remote monitoring, and a variation of ISFETs are currently being used as continuous glucose monitors for diabetes patients. While ISFETs are not a new development in the field of microelectronics, their use as wearable devices has recently become relevant. The goal of this project is primarily to …

Design And Analysis Of A Discrete, Pcb-Level Low-Power, Microwave Cross-Coupled Differential Lc Voltage-Controlled Oscillator, Pavin Singh Virdee

Master's Theses

Radio Frequency (RF) and Microwave devices are typically implemented in Integrated Circuit (IC) form to minimize parasitics, increase precision and tolerances, and minimize size. Although IC fabrication for students and independent engineers is cost-prohibitive, an abundance of low-cost, easily accessible printed circuit board (PCB) and electronic component manufacturers allows affordable PCB fabrication.

While nearly all microwave voltage-controlled oscillator (VCO) designs are IC-based, this study presents a discrete PCB-level cross-coupled, differential LC VCO to demonstrate this more affordable and accessible approach. This thesis presents a 65 mW, discrete component VCO PCB with industry-comparable RF performance. A phase noise of -103.7 dBc/Hz …

Multifamily Complex Smart Locks For Property Management And Tenant Security, April Mills, Allen Chen, Dana Kumamoto, Michael Cook

Mechanical Engineering

Maintaining and managing hundreds of locks and physical keys for an apartment complex can be time consuming and costly, especially when the apartments turn over to new tenants. Our goal was to develop a smart door lock that is compatible with Obodo’s management app for apartment complexes to make accessing apartments secure and simpler for tenants and easier to manage for owners.

We designed and manufactured one smart door lock that is powered with four AA batteries and utilizes a dynamic NFC device and Bluetooth technology. The board can enter a sleep mode which reduces power consumption. The dynamic NFC …

X-Band Rf Transmitter Design For Multi-Purpose Small Satellite Communication Operations, Omer F. Gumus

Master's Theses

This thesis provides a description of the analysis, design, and tests of an X-band RF Transmitter communication system for small satellites. X-band transmitter systems are becoming popular in the upcoming deep space missions. Most of the deep-space ground stations have been using X-band frequencies to receive or transmit signals. The X-band (<10 GHz) can offer lower atmospheric losses and up to a couple of Mbps data rates for multiple satellite operations. Nowadays, many small satellites have been using frequency bands such as VHF, UHF, L, and S-band frequencies for communication. From deep space to the ground station, the low-frequency ranges are inadequate in providing Mbps level data rates and enough bandwidth for deep space missions.

The main focus of this thesis was the development of the subsystems such as gain block amplifier, Mixer, Bandpass Filter, and RF power amplifier. The subsystems were designed separately, then they were connected together to perform an end-to-end system test. One of the thesis aims is to design …

Model-Based Design Of An Optimal Lqg Regulator For A Piezoelectric Actuated Smart Structure Using A High-Precision Laser Interferometry Measurement System, Grant P. Gallagher

Master's Theses

Smart structure control systems commonly use piezoceramic sensors or accelerometers as vibration measurement devices. These measurement devices often produce noisy and/or low-precision signals, which makes it difficult to measure small-amplitude vibrations. Laser interferometry devices pose as an alternative high-precision position measurement method, capable of nanometer-scale resolution. The aim of this research is to utilize a model-based design approach to develop and implement a real-time Linear Quadratic Gaussian (LQG) regulator for a piezoelectric actuated smart structure using a high-precision laser interferometry measurement system to suppress the excitation of vibratory modes.

The analytical model of the smart structure is derived using the …

Design And Analysis Of N-Path Filter For Radio Frequencies, Nathan M. Bergen

Master's Theses

Due to the growth of wireless communication many communication frequencies have grown increasingly dense. This density requires higher Q-factor to receive only the signal of interest. With the rise of smaller integrated circuits previous solutions used for filtering have become viable again. This paper explores whether the N-path filter is viable in the modern day for radio frequency receiver purposes. A non-differential N-path filter was created by utilizing Cadence Virtuoso with a working center frequency range of 750MHz to 1GHz while using TSMC technology. The desired quality factor of over 1,000 was reached while maintaining a total area of 800 …

Design And Characterization Of Standard Cell Library Using Finfets, Phanindra Datta Sadhu

Master's Theses

The processors and digital circuits designed today contain billions of transistors on a small piece of silicon. As devices are becoming smaller, slimmer, faster, and more efficient, the transistors also have to keep up with the demands and needs of the daily user. Unfortunately, the CMOS technology has reached its limit and cannot be used to scale down due to the transistor's breakdown caused by short channel effects. An alternative solution to this is the FinFET transistor technology, where the gate of the transistor is a three dimensional fin that surrounds the transistor and prevents the breakdown caused by scaling …

Design Of An Ultra-Wideband Frequency-Modulated Continuous Wave Short Range Radar System For Extending Independent Living, Toai-Chi Nguyen

Master's Theses

Falls in the disabled and elderly people have been a cause of concern as they can be immobilized by the fall and have no way to contact others and seek assistance. The proposed frequency modulated continuous wave (FMCW) short range radar (SRR) system, which uses ultra-wideband (UWB) signals can provide immediate assistance by monitoring and detecting fall events. The unique characteristics of this system allow for a frequency-based modulation system to carry out triangulation and sense the location of the fall through the usage of a continuous chirp signal that linearly sweeps frequency. This project focuses on the development, design …

An Exploratory Study Of Pulse Width And Delta Sigma Modulators, Logan B. Penrod

Master's Theses

This paper explores the noise shaping and noise producing qualities of Delta-Sigma Modulators (DSM) and Pulse-Width Modulators (PWM). DSM has long been dominant in the Delta Sigma Analog-to-Digital Converter (DSADC) as a noise-shaped quantizer and time discretizer, while PWM, with a similar self oscillating structure, has seen use in Class D Power Amplifiers, performing a similar function. It has been shown that the PWM in Class D Amplifiers outperforms the DSM [1], but could this advantage be used in DSADC use-cases? LTSpice simulation and printed circuit board implementation and test are used to present data on four variations of these …

Simulation Of An Sp8t 18 Ghz Rf Switch Using Smt Pin Diodes, Andre De Souza Vigano

Master's Theses

Radio frequency (RF) and microwave switches are widely used in several different applications including radar, measurement systems, telecommunications, and other areas. An RF switch can control a radar’s transmit vs. receive mode, select the operating band, or direct an RF signal to different paths. In this study, a single pole eight throw (SP8T) switch using only Surface Mount (SMT) components is designed and simulated in Keysight’s Advanced Design System (ADS). Single pole eight throw is defined as one input and eight possible outputs. A star network configuration with series-shunt PIN diode switches is used to create the 8-way RF switch. …

High Speed, High Current Monitoring System, Nicolette Lila Ray

Electrical Engineering

Electronics testing requires lengthy data collection and analysis. Streamlining at least part of this process allows resource reallocation, and faster data processing. Verifying a signal’s efficiency is key specification for a component’s datasheet. This project focuses on streamlining data collection when measuring a device’s output current. It combines amplifier design and digital interfacing to perform monitor a device’s output current. A computer-enable interface displays a graphical output current representation. It ensures accurate, high speed, high current measurements while removing a person’s need to manually plot data after testing. A new testing method provides room for company and product growth with …

Dc-Dc Converter For Electric Vehicle, Jason Y. Zhou, Nicholas James Mah

Electrical Engineering

In this work, a DC-DC converter is designed for an electric vehicle. The DC-DC converter is designed to provide 500W with a 200-400V input and a 12-15V adjustable output. Electric vehicle sales are beginning to increase in popularity and the need for DC-DC converters to siphon power from the tractive system is not yet fully satisfied, especially for single-seater class vehicles. Additionally, improving performance in efficiency without sacrificing wide input voltage range can benefit future DC-DC converter designs. In the end, a forward active clamp DC-DC converter is designed and tested. Additionally, spreadsheet calculators, LTSpice simulations, and Matlab scripts were …

Experimental Study And Modeling Of The Gm-I Dependence Of Long-Channel Mosfets, Michael Fong Cheng

Master's Theses

This thesis describes an experimental study and modeling of the current-transconductance dependence of the ALD1106, ALD1107, and CD4007 arrays. The study tests the hypothesis that the I-gm dependence of these 7.8 µm to 10 µm MOSFETs conforms to the Advanced Compact Model (ACM). Results from performed measurements, however, do not support this expectation. Despite the relatively large length, both ALD1106 and ALD1107 show sufficiently pronounced ‘short-channel’ effects to render the ACM inadequate. As a byproduct of this effort, we confirmed the modified ACM equation. With an m factor of approximately 0.6, it captures the I-gm dependence with sub-28% maximum error …

Furnace System Improvements, Kenji K. Anzai, Ethan Fedor, Patrick Zailaa

Mechanical Engineering

This Final Design Review (FDR) documents the work done by the group to manufacture the system to deliver improvements to the furnace in the Cal Poly microfabrication laboratory (better known as the cleanroom). The document describes the material covered in the Scope of Work (SOW), including background research, customer needfinding, and the problem statement, material associated with concept development and selection for Preliminary Design Review (PDR), material detailing the design and manufacturing plan of the system for Critical Design Review (CDR), and new material detailing the manufacture of the system for FDR.

Research done for the SOW resulted in a …

Adaptation Of Vt-Dbr Lasers For Lidar, Luke Horowitz

Master's Theses

Vernier Tuned Distributed Bragg Reflector (VT-DBR) lasers have had great success in the field of Swept-Source Optical Coherence Tomography (SS-OCT) due to their continuous and nearly 40 nm wavelength tuning range in a single longitudinal mode. Fast sweeps allow for real time imaging with micrometer resolution at a distance of a few centimeters. While this laser has proven quite useful as a medical imaging tool via OCT, it has yet to similarly prove itself for general light detection and ranging (LIDAR) applications due to range limitations that arise from a finite laser coherence length. The goal of this thesis is …

Flexible Custom Electric Skateboard, Caleb Adam Kelsay

Electrical Engineering

At Cal Poly traveling long distances only accessible by foot such as across campus or from the car park to class can be tiring and time-consuming. While not physically demanding, the trek consumes time in our tight college life schedule. To improve our time efficiency this project provides a relatively lightweight, powered solution to quickly and effectively travel long distances while maintaining full control and safety even on hills, a current limitation of traditional skateboards.

This electric skateboard includes the battery capacity to travel all around campus on a single charge with a compact and flexible skateboard design that provides …

Characterization Of Flexible Hybrid Electronics Using Stretchable Silver Ink And Ultra-Thin Silicon Die, Joshua A. Ledgerwood

Master's Theses

Flexible Hybrid Electronics (FHEs) offer many advantages to the future of wearable technology. By combining the dynamic performance of conductive inks, and the functionality of ultra-thinned, traditional IC technology, new FHE devices allow for development of applications previously excluded by relying on a specific type of electronics technology.

The characterization and reliability analysis of stretchable conductive inks paired with ultra-thin silicon die in theµm range was conducted. A silver based ink designed to be stretchable was screen printed on a TPU substrate and cured using box oven, conveyor convection oven, and photonic curing processes. Reliability tests were conducted including a …

Inquiry Of Graphene Electronic Fabrication, John Rausch Greene

Master's Theses

Graphene electronics represent a developing field where many material properties and devices characteristics are still unknown. Researching several possible fabrication processes creates a fabrication process using resources found at Cal Poly a local industry sponsor. The project attempts to produce a graphene network in the shape of a fractal Sierpinski carpet. The fractal geometry proves that PDMS microfluidic channels produce the fine feature dimensions desired during graphene oxide deposit. Thermal reduction then reduces the graphene oxide into a purified state of graphene. Issues arise during thermal reduction because of excessive oxygen content in the furnace. The excess oxygen results in …

Active Charge Balancing For Cardiac Stimulation, Maci Miri

Electrical Engineering

Worldwide, there are about 3 million people who have pacemakers, with 10,000 new implantations of ICD’s each month. [heart.org] Due to the gravity and importance of the function that ICD’s provide, these devices must be extremely reliable and highly effective. However, because of the high tolerances of IC manufacturing, stimulation circuits for pacemakers may be slightly unmatched and over time, may have a net DC charge applied to the tissues in the heart. Extra charge pumped into body tissues is dangerous for the patient’s health; the pH of the tissue can be raised and corrosion of the stimulating electrodes may …

Out-Of-Loop Compensation Method For Op-Amps Driving Heavy Capacitive Loads, Shubham Gandhi

Master's Theses

It is well known that real op-amps do not share most of the desirable characteristics of an ideal one, particularly those of gain and output impedance. When presented with a capacitive load, such as a MOSFET or ADC, feedback in an op-amp circuit can quickly become unstable. This thesis studies and characterizes an op-amp’s output impedance and how its interaction with this type of load creates a parasitic pole which leads to instability. Applying ideas from feedback control theory, a model for studying the problem is developed from which a generalized method for compensating the undesirable circumstance is formulated.

Even …

Wide-Band Gap Devices For Dc Breaker Applications, Olukayode O. Sodipe

Master's Theses

With the increasing interest in wide-band gap devices, their potential benefits in power applications have been studied and explored with numerous studies conducted for both SiC and GaN devices. This thesis investigates the use of wide-band gap devices as the switching element in a semiconductor DC breaker. It involves the design of an efficient semiconductor DC breaker, its simulation in SPICE, construction of a hardware prototype and the comparative study of SiC and Si versions of the aforementioned breaker. The results obtained from the experiments conducted in the process of concluding this thesis show that the SiC version of the …

A Feed Forward Circuit For Jitter Attenuation On High-Speed Digital Signals, Eric Rule

Electrical Engineering

In the age of high-speed digital circuitry, there exists a need for clean, precise clock signals. In generating and distributing clock signals throughout a circuit, unwanted jitter can become a serious issue. A common technique for attenuating jitter uses phase-locked-loops to treat the signal, but as the clock frequency increases, so does the cost and complexity of the designs. Following the research completed by Dr. Tina Smilkstein [1], this project examines a purely feed-forward technique for attenuating jitter that is low-complexity and robust, and aims to design an integrated circuit that implements the technique.

Mohat Tool To Illustrate Diode And Transistor Modes Of Operation Using Ltspice, Getu D. Engdaw

Electrical Engineering

This project develops a tool to identify the modes of operation of diodes and transistors in a circuit. The MoHAT tool receives schematics or circuit files generated from LTspice, and it determines the state of each diode and transistor. This tool illustrates diodes, BJT and MOS regions of operations using text or graphics accordingly. The tool also suggests necessary adjustments to switch from one mode of operation to another upon users request. Furthermore, the tool specifies if a transistor functions in amplification region. The MoHAT tool compares the nodal voltages of an element and determines the mode of operation.

Phase Locked Loop Integrated Circuit, Scott Buchanan, Jonathan Bonello

Electrical Engineering

No abstract provided.

Chipper: Capacitive Bed Occupancy Sensing For An Intelligent Alarm Clock, David Levi

Electrical Engineering

What if your alarm clock knew when you got out—and stayed out—of bed? Current alarm clocks happily let you go back to bed after turning them off. In this project, I build an alarm which only stops ringing when you get out bed, and starts ringing again if you lie back in bed.

This project uses capacitance to detect bed occupancy. A person on or near the bed creates a tiny, picofarads level increase in capacitance, as seen by a sensor placed under the mattress. A microprocessor interprets this signal, and also drives an audio alarm. Shielding of the sensor …

Design And Fabrication Techniques Of Devices For Embedded Power Active Contact Lens, Errol Heradio Leon

Master's Theses

This thesis designed and fabricated various devices that were interfaced to an IC for an active contact lens that notifies the user of an event by detection of an external wireless signal. The contact lens consisted of an embedded antenna providing communication with a 2.4GHz system, as well as inductive charging at an operating frequency of 13.56 MHz. The lens utilized a CBC005 5µAh thin film battery by Cymbet and a manufactured graphene super capacitor as a power source. The custom integrated circuit (IC) was designed using the On Semiconductor CMOS C5 0.6 µm process to manage …

Characterization Of Two Vernier-Tuned Distributed Bragg Reflector (Vt-Dbr) Lasers Used In Swept Source Optical Coherence Tomography (Ss-Oct), Greg M. Bergdoll

Master's Theses

Insight Photonic Solutions Inc. has continued to develop their patented VT-DBR laser design; these wavelength tunable lasers promise marked image-quality and acquisition time improvements in SS-OCT applications.

To be well suited for SS-OCT, tunable lasers must be capable of producing a highly linear wavelength sweep across a tuning range well-matched to the medium being imaged; many different tunable lasers used in SS-OCT are compared to identify the optimal solution.

This work electrically and spectrally characterizes two completely new all-semiconductor VT-DBR designs to compare, as well. The Neptune VT-DBR, an O-band laser, operates around the 1310 nm range and is a …

Energy Harvesting From Exercise Machines: Lt8705 Dc-Dc Conversion For Elliptical Trainers, Braden Burk, Raj Bhula, Nathan Mckay

Electrical Engineering

Cal Poly’s Energy Harvesting from Exercise Machines (EHFEM) program aims to power the grid using human energy harvested from exercise machines in its gym. Doing so could save the school money and increase the total supply of power available on the grid. This document belongs to one of many groups attempting to design a suitable DC-DC conversion system for an elliptical trainer using an LT8705 Four-Switch Buck-Boost converter. Past teams have built other converters and developed system compatibility characteristics such as filtering, safety, and stability for interfacing components. These teams fall into one of two departments in EHFEM: DC-DC Conversion …

Buck Converter, Bowen Liu

Electrical Engineering

The recent sustainable energy growth triggered a huge power electronics demand, specifically related to power conversion. My senior project is a design of a buck converter which steps down the voltage from photovoltaic cells ranging from 5 to 40V to a rechargeable battery with 5V. This converter has a high enough power efficiency to effectively convert the energy harnessed from PV panels.