Analog/RF IC is an art which has high design flexibility - SOP for PHD in analog IC in USA

check grammar & words errors and give advice on structure & content

Statement of Purpose

I love analog/Radio-Frequency(RF) Integrated Circuits(IC) because it calls for understanding of multiple disciplines. It urges me to learn as much as possible and to address problems from perspectives of different fields. Besides, analog/RF IC is an art which has high design flexibility. One can never reach a perfect product because of many design trade-offs. What I yearn for is to enrich my knowledge and to design the initiative circuits to challenge the limits. Finally, our daily life is permeated with IC products. Studying this sphere that is closely geared to people's life makes me highly excited and motivated.

I have finished my master's education in A University, one of the top two universities in my country. In my fist year(2012-2013), I took several important courses like Analog Large Scale Integration, The Design of CMOS RF IC and IC Design and Practice, which gave me basic knowledge of circuits analysis and design and made me familiar with the whole analog IC design process.

I had been under Professor Taohong Shi's supervisor for two and a half years. I chose Phase Lock Loop(PLL) as my research since it is widely used and requires knowledge of mixed-circuits design, system design, and RF circuits design. I implemented an 80 - 83 GHz digitally-controlled oscillator in 65nm CMOS. At such a high frequency, I combined Electronic Design Automation(EDA) tools like Cadence, Caliber, High Frequency Structure Simulator(HFSS) and Advanced Design System(ADS) together to carry out the oscillator. The most challenging thing was to design and get the simulation property of floating metal strip slow-wave structure underneath the transmission line and inductance used to realize frequency tuning in LC oscillator. HFSS was used to solve the problem. After a half year's studying tutorial manual, searching discussion about HFSS design examples on EDA forums, consulting seniors for simulation setting advice and reviewing Maxwell field equations, I became confidence in the EM simulating results and gained in-depth understanding and experiences. This work is published in Science Citation Index(SCI) journal, whose impact factor is around one point six.

In addition, I had redesigned a 40 GHz integer-N PLL. To get a deeper understanding of PLL, I sit in Professor Boogeun Chee's class - PLL Design and Clock/Frequency Generation. I applied what I learnt in class to project and got a lot from my project. I became sophisticated in the use of EDA tools. I came to know the importance to study the advanced semiconductor process document. For example, knowing parasitic parameters in the document such as sheet resistance and parasitic capacity on different materials helps a lot in the process of trade-offs between resistance and capacity. Besides, It is important to comprehend the principles of EDA simulators - ADS, HFSS and Spectre - in order to improve accuracy and efficiency by Choosing the appropriate simulation method according to the target circuits. For instance, S-parameter simulator first gets the Direct-Current(DC) operation points by solving circuits with Kirchhoff equations and then linearizes the circuits at the DC point. With that in mind, I will never try to inspect circuits' large-signal model by S-parameter simulator. By applying my acquired theoretical and conceptual skill, I successfully worked out the PLL and gained deep understanding of PLL design. This work was applied in my seniors' dissertations and papers.

I have been working as a RF engineer since I graduated in 2015. I grow intellectually and emotionally in my work. And this experience confirms what I really want to do is academic research. My work contains designing a board-level Radio Frequency Identification(RFID) transceiver, studying datasheets of different chips, drawing Printed Circuit Board(PCB) and testing. The RFID transceiver has experienced more than ten times iterations. The testing results and analysis of the testing phenomena guide us how to improve in the next iteration. I have been sophisticated in the utilize of testing instruments and accumulated precious testing experience which can not be learned by other approaches. I also have deeper understanding of system design. What's more, I learn the importance of team work. At first, I complained some low-tech work such as redrawing PCB again and again, soldering PCB and compiling tedious documents. But looking back afterwards, I see that only each one in the team makes contribution can the whole project go forward smoothly. I still remember that the RFID reader went wrong before certification on a Friday night. All people on the team including software, hardware and structural engineers worked twenty hours nonstop to solve the problem. The best result always comes from a solidly aligned team.

However, I am not satisfied with my work in that it is based on board-level circuits. I am eager to know what the structure is inside the chips and I am thirsty to design my own chips. I am highly interested in transceiver, PLL and other analog/RF IC. My true career interests are IC research. Based on my background and enthusiasm in IC design, I confirmedly believe that I can go much further in my future PHD study. Apart from my work, my personality occupies me to take PHD program smoothly. I am optimistic , adaptable and very tenacious. I once completed half-marathon in two hours and cycled three hundred kilometer in three days.

___ University's Analog/Mixed-signal area and RF/Microwave/Millimeter-wave Circuits and systems area in Integrated Electronics attract me most, largely because of the outstanding faculty and perfect match for my career aspiration. I am particularly interested in Professor ____'s and Professor ____'s lab. They both have strong academic and industry background and their students have published a lot in top research conferences and journals. Together, both of their cutting edge research and deep understanding on Integrated Electronics would make my experience at ____ University a challenging and enjoyable one.

Wang, since you already have a previous masters degree tucked under your belt, going all the way back to your college days for a reference is no longer required in this instance. You should provide a summary of that section of your academic life because it only laid out the foundation for your career. The actual focus of your current discussion should be on how your masters degree has improved your career to this point, where you now require a PhD in order to function at a higher capacity on the job. Refer to a potential dissertation thesis in relation to your masters thesis or a fresh research project that better aligns your more advanced academic interests with your PhD desires. Start your essay at paragraph 2, then bring up paragraph 5, improve on the presentation and information, and present a potential thesis statement before discussing why this PhD university is the best choice for you. That would create a more appropriate draft essay for your purposes.

@Holt,
Your suggestion enlightens me and I did not realize the problem when I structured my writing. However, there are difficulties because my job doesn't match my masters exactly while my application concurs with my academic study. So, if I focus on how my masters degree has improved my career to this point, I can not show my professional ability fully. They have connections but my academy study address problems in a deeper way.