SJ Semiconductor (盛合晶微半导体)

SJ Semiconductor (SJSemi, 盛合晶微半导体) is a leading MEOL (Middle-End-of-Line) foundry headquartered in Jiangyin, Jiangsu Province, China. Founded in August 2014 as a joint venture, the company specializes in advanced 12-inch wafer bumping, redistribution layer (RDL) fabrication, wafer-level packaging, and 3D chiplet integration technologies. SJSemi was among the first companies in mainland China to mass-produce 12-inch bumping and to offer 14nm advanced-node bumping services. The company operates at the intersection of traditional semiconductor packaging and next-generation heterogeneous integration, enabling advanced chiplet and multi-die designs. It employs approximately 5,968 people and is listed on the Shanghai Stock Exchange (SSE: 688820).