Samsung Electronics said on Wednesday it has named Jun Young-hyun as the new head of its memory chip business and co-CEO of the company, while Han Jin-man will become the head of the foundry business with a promotion to president.

Samsung also named Nam Seok-woo who has been head of chip factory engineering and operations as the Chief Technology Officer of the foundry business.

The major reshuffle of its top rank comes as shares of the tech giant have steadily fallen since August on investor concerns that it is lagging its rivals in supplying high-end chips to Nvidia in the booming AI market.

Jun, the new memory chip head, was brought in to head the semiconductor division in May in what the company said was a move to tackle a "chip crisis".

In early October, he apologised for its disappointing performance and said its AI chip business with an unidentified major customer was hit by a delay.

The appointments announced on Wednesday also include a new president of management strategy at the Device Solutions (DS) division.

Park Hark-kyu, president and CFO of Samsung Electronics, will move to the Business Support Task Force, while his successor has not yet been named.

Samsung's semiconductor business suffered a 40% quarter-on-quarter profit plunge in the July-September quarter, as the company has struggled to catch up with rivals TSMC and SK Hynix that posted record third-quarter earnings on the back of the artificial intelligence boom.

Worries about the impact of U.S. tariffs under the impending new administration of U.S. President-elect Donald Trump have also weighed on Samsung shares, which have fallen more than 25% so far this year, making them one of the worst performers among major chipmakers.

In rare public comments, Samsung Electronics Chairman Jay Y. Lee said earlier this week that the company is facing unprecedented challenges.

"I am fully aware that there are grave concerns about the future of Samsung recently," he said during the final hearing of an accounting fraud trial where he is a defendant.