(Reuters) - Employees of Freescale Semiconductor who were on a Malaysia Airlines flight presumed to have crashed were doing sophisticated work at the U.S. chipmaker, a company spokesman said on Sunday.

The 20 Freescale employees, among 239 people on flight MH370, were mostly engineers and other experts working to make the company's chip facilities in Tianjin, China, and Kuala Lumpur more efficient, said Mitch Haws, vice president, global communications and investor relations.

"These were people with a lot of experience and technical background and they were very important people," Haws said. "It's definitely a loss for the company."

None of Austin, Texas-based Freescale's most senior executives were on board the Boeing Co 777-200ER airliner that vanished from radar screens about an hour after it took off from Kuala Lumpur for Beijing on Saturday.

The employees who were on board, 12 from Malaysia and eight from China, came from a range of disciplines and they were part of a broad push by Chief Executive Officer Gregg Lowe to make Freescale more efficient and cost effective, Haws said.

Top-quality engineers are hard to come by for chipmakers and other technology companies, and losing them can have a major impact on business, regardless of their seniority.