Prosecutors indicted a former employee of Samsung Electronics on Wednesday on charges of leaking key semiconductor technologies of the tech giant to a Chinese company in return for money, officials said.

The Seoul Central District Prosecutors Office indicted the employee surnamed Kim, who formerly served as a department head at Samsung, under physical detention on charges of violating the industrial technology protection law, prosecution officials said.

Kim is accused of having stolen Samsung's information on the manufacturing of the 18-nano DRAM semiconductor, a state-designated core technology, and transferred it to Chinese semiconductor manufacturer ChangXin Memory Technologies (CXMT) to be used for its product development.

Prosecutors suspect Kim handed data on seven key technologies in semiconductor manufacturing and others over to CXMT in return for tens of millions of dollars when he moved to the Chinese firm in 2016.

Kim is also suspected of having some 20 technicians from Samsung and other firms move to the Chinese firm, offering them high financial rewards.

The Chinese firm, which was a novice in 2016, has rapidly grown into a major DRAM manufacturer, narrowing technology gaps with its competitors in South Korea and the United States.

Prosecutors also indicted another former employee of a South Korean semiconductor equipment supplier to Samsung under physical detention on charges of leaking key technologies of his former company to CXMT in collusion with Kim.