Creating exotic novel materials with plasma is topic of new Tomorrow’s PSE Leaders webinar
Using plasma to create exotic novel materials with enhanced properties that can find uses in refractory applications, medical applications, fast-breeders, lightweight armors, ballistic armors, cutting tools and high-temperature thermoelectric conversion is the topic of a new webinar that’s part of a bimonthly series called Tomorrow’s PSE Leaders, sponsored by Alabama’s Future Technologies & enabling Plasma Processes (FTPP) project.
Synthesizing these materials is the most interesting part of his research, says Dr. Kallol Chakrabarty, a postdoctoral researcher at the University of Alabama at Birmingham (UAB). Dr. Chakrabarty’s webinar, “Microwave Plasma CVD Synthesis of Superhard CNOB Materials,” will discuss using microwave plasma chemical vapor deposition (MPCVD) to synthesize superhard materials.
“One of the most adventurous and intellectually stimulating parts of this journey is optimizing the experimental conditions to achieve the desired material,” says Dr. Chakrabarty. “This requires systematically varying key parameters, such as microwave power, chamber pressure, substrate temperature, and gas flow rates, to find the perfect balance that facilitates the growth or fabrication of the target material.”
what is superhard?
The term superhard is used to describe materials that have a measured hardness of at least 40 GigaPascals (GPa). Chemical vapor deposition is the parent to a family of processes where a solid material is deposited from a vapor by a chemical reaction occurring on or in the vicinity of a normally heated substrate surface.
CNOB materials are based on the light elements of carbon, oxygen, nitrogen and boron. In MPCVD, reactive gases are introduced in a vacuum chamber, and microwave is used to break up gas molecules and create plasma. Plasma is a gas consisting of electrons, ionized molecules, neutral molecules, neutral and ionized fragments of broken-up molecules and excited molecules. In this process, molecular fragments readily bond to other atoms to form a coating at the substrate’s surface.
In Dr. Chakrabarty’s project, hydrogen (H2) was used as the carrier gas, and diborane (B2H6), nitrogen (N2), and methane (CH4) were used as reactive gas. Different experimental conditions were established to find out the best conditions to synthesize superhard CNOB materials such as B50C2, BC10N, etc., by changing microwave power, chamber pressure, substrate temperature and gas flow rates.
“Each adjustment and fine-tuning step brings a new set of challenges, unexpected results and valuable insights into the complex interactions that occur during the synthesis process,” he says. “In my case, optical emission spectroscopy serves as a vital diagnostic tool, providing real-time insights into the plasma chemistry and aiding in the fine-tuning of key parameters.”
theory to reality
Dr. Chakrabarty is particularly gratified when his work turns theory into reality.
“There is a deep sense of accomplishment when, after numerous trials and careful iterations, you succeed in synthesizing the very material that a theoretical colleague had predicted. Seeing theoretical models and simulations come to life as tangible, real-world materials is immensely gratifying,” he says. “This moment represents the bridge between theory and experiment and underscores the collaborative, interdisciplinary nature of scientific research.”
Dr. Chakrabarty received his doctorate in physics from UAB in summer 2023. He was mentored for his doctorate at UAB by Dr. Shane Aaron Catledge, associate physics professor and graduate program director. His postdoctoral mentor is Dr. Yogesh K. Vohra, UAB professor university scholar in physics , and associate dean in the College of Arts and Sciences. He aspires to work as a research scientist in a university, a national laboratory, or a research-driven industry.
His work is funded by FTPP, an Alabama coalition of nine universities and a research corporation supported by a $20 million grant from the National Science Foundation (NSF) and managed at The University of Alabama in Huntsville (UAH). FTPP aims to transition plasma research into agricultural, manufacturing, space science, space weather prediction and other applications, establishing Alabama as a Southeastern regional hub for plasma science expertise and creating thousands of high-paying technical careers in the state and region.
Idea exchange
His association with FTPP has been fruitful, Dr. Chakrabarty says.
“FTPP meetings offer a unique and valuable opportunity to engage with a smaller, close-knit group of researchers, fostering more meaningful interactions and in-depth discussions. These focused gatherings allow for productive conversations, exchange of ideas, and constructive feedback on ongoing research,” he says. “The collaborative atmosphere makes it easier to explore shared research interests, gain new perspectives and develop professional connections essential for scientific growth and innovation.”
Within FTPP’s established milestones, “I had the flexibility to explore and implement my ideas to help achieve its goals,” says Dr. Chakrabarty. “As an experimental researcher, this has been incredibly rewarding. What truly makes this project unique is its perfect balance between collaborative teamwork and independent research, creating an ideal environment for innovation and professional growth.”
In addition to Dr. Catledge and Dr. Vohra, Dr. Chakrabarty acknowledges the support, guidance and mentorship of Dr. Yasmeen Haque, Dr. Susanta Kumar Das and Dr. Sharif Md. Sharafuddin from the Department of Physics, as well as Dr. Muhammed Zafar Iqbal from the Department of Computer Science and Engineering, at Shahjalal University of Science and Technology, Bangladesh, during his Master of Science and Master of Philosophy studies and research. He says he is also grateful to the teachers who guided him through various stages of his academic journey and made a lasting impact.
“I want to thank my mother, Lucky Chakrabarty, and father, Kiriti Bhushan Chakrabarty, for their love and unbelievable support throughout my life. I thank them for giving me the strength to achieve my goals and go ahead with my dream,” says Dr. Chakrabarty.
“I am incredibly grateful to my beloved wife and best friend, Deblina Das, a doctoral student in physics at UAB, for her unconditional support, love, care, and understanding. We began our undergraduate journey together in the Department of Physics at Shahjalal University of Science and Technology. Throughout our time there, we supported each other in our academic pursuits, including preparing for the Graduate Record Examinations. Now, we are thrilled to be fulfilling our shared dream of pursuing higher education and conducting experimental research in the USA, a goal we worked toward side by side.”