Tokyo Tech-ULVAC won the Best Poster Presentation Award at Int. Conf. ISPlasma2024

At the Tokyo Institute of Technology's ULVAC Advanced Technology Collaborative Research Center, we are conducting joint research with the aim of advancing plasma processing equipment through emission spectroscopy measurement, focusing on reactive plasmas, which are often applied in the manufacturing processes of semiconductor integrated circuits. We are working on plasmaexperiments and theoretical modeling of excitation kinetics in the plasmas. In March 2023, our joint research was selected as a featured presentation at the spring meeting of the Japan Society of Applied Physics.

As a follow-up report, a group led by Kenta Ishi, a second-year master's student in the electrical and electronics course at the time, conducted research on the density distribution of excited states determined by emission spectroscopy experiments in nitrogen inductively coupled plasma. We improved and developed a theoretical excitation-kinetic model , and confirmed the validity of our model through comparison with experiments. The results were presented as a poster at the international conferences ISPlasma2024/IC-PLANTS2024/APSPT-13, where they were highly praised and received the Best Poster Presentation Award. Please refer to the Best Poster Presentation Award Winners section of the web page.　

It is already understood in low-temperature plasma society that in low-temperature discharge plasmas of molecular gases such as nitrogen, the electron energy distribution function (EEDF) deviates from the Maxwellian distribution. We started modeling from the respect where EEDF is described by the Boltzmann equation, which includes inelastic electron-collision processes with the vibrational population of nitrogen neutral molecules to form the vibrational distribution function (VDF). Based on the calculated EEDF and VDF, electronically-excited states must be considered their populations. I believe that the research has achieved a certain degree of success in solving this problem.

In this field of nitrogen plasma, which is crucial in the fields of electronic/semiconductor engineering, environmental engineering, and geoelectromagnetism, there is outstanding academic accumulation in European countries such as Portugal, the Netherlands, and the Czech Republic, while we were lagging behind due in part to a decrease in the number of research groups. We believe that our current research is at a level that will allow us to make up for this delay and move forward. Similar methods are expected to be applied to modeling various process plasmas in the future.

In this way, Tokyo Tech “ULVAC Advanced Technology Collaborative Research Center” are conducting joint research with the aim of improving the performance of semiconductor processing equipment. We have achieved the above results at this time, and our confidence in our research results has deepened. We will continue to make even more efforts toward further advancement and social implementation. We look forward to your continuous guidance and support.