Dr. Yifeng Chen is the vice president of technology in Trina Solar, and vice president of State Key Lab of PV Science and Technology in China. He received his B.S. degree in optics in Sun Yat-Sen University in 2004, and his PhD degree of physics in Sun Yat-Sen University in 2013 on numerical simulation and device physics of high-efficiency c-Si solar cells under the supervision of Prof. Hui. Shen. From 2011 to 2012, he worked as a co-training PhD under the supervision of Dr. Pietro. Altermatt in the Leibniz University of Hanover, Germany. In 2013 he joined Trina Solar as technical assistant of Dr. Pierre Verlinden. Since 2014, Dr. Chen became the group leader of high efficiency solar cells R&D in Trina Solar, leading the team to develop high efficiency PERC, and the first inline hydrogenation tool to deactivate B-O complex in China, the first total-area 25% IBC cell with dimension of 156.75mm (25.04% by JET in 2018), and 24.58% and 23.22% bifacial tunnel oxide passivated contact “i-TOPCon” cell (cited in NREL Efficiency Chart and in Prof. Green’s Efficiency Table). Since 2020, Dr. Chen became the head of technology department, lead the group to develop champion 24.5% p-type PERC and 25.5% n-type i-TOPCon cells on 210mm wafers, modules with power from 400 to 700W (with champion aperture module efficiency of 24.2%), and transfer the technology to mass production. Dr. Chen is the winner of “SiliconPV Award” (3^rd SiliconPV conference, Hameln, Germany, 2013), “Young Researcher Award” (WCPEC-6, Kyoto, Japan, 2014), and the IEEE Stuart R. Wenham Young Professional Award (IEEE PVSC, San Juan, the USA, 2023).