China’s southern tech hub of Shenzhen wants to double the value of its existing chip sector within three years as part of a broader push to improve the country’s self-sufficiency in core technologies. Shenzhen, known as China’s Silicon Valley, announced a plan to build “an influential cluster” for the semiconductor industry by 2025, including the development of leading national capabilities in manufacturing, packaging and testing of chips. By 2025, Shenzhen aims to develop a semiconductor industry that can bring in 250 billion yuan (US$37.5 billion) in annual sales, compared to the 110 billion yuan in revenue last year, according to…