High-tech semiconductor equipment manufacturer KLA Corp. expanded its plans for a research and investment center in Washtenaw County that will serve as its second headquarters.

The Milpitas, Calif.-based company, which supplies process control and yield management systems for the semiconductor industry, plans to invest $150 million — up from $71.1 million — and create 600 jobs, according to John McLaughlin, the Ann Arbor site leader for KLA.

Plans are in progress to build a a 230,000-square-foot building for office and "clean" R&D space in Ann Arbor Township, McLaughlin said. "Clean" here means they won't use any "harmful chemicals" on the land, he added.

The latest plan expands on a previously announced R&D center that would have created 500 jobs.

KLA bought the 17-acre Ann Arbor Technology Park site from the University of Michigan for approximately $27 million.

In advance of the headquarters' expected summer 2021 completion, KLA opened a 58,000-square-foot, leased office June 11 in Ann Arbor near Plymouth Road and U.S.-23. It has room for 250 employees on a four-year lease.

"The strategy is to fill this space in the next two years so that we are on the ground running when we open up the permanent campus," McLaughlin said.

The Michigan Strategic Fund on Tuesday approved an increase in a state grant to assist with the expanded project. It will now get $2.5 million through the Michigan Business Development Program, up from the previously announced $1.5 million, according to the MEDC memo.

There has been no change in the state's October decision to also support the project with about $16.2 million over eight years through a Good Jobs for Michigan withholding tax capture.

"Among the decisive reasons for building a major R&D hub in Michigan are Ann Arbor and the Detroit metropolitan area's attractive talent pool, relative low-cost of living (compared to the San Francisco region where KLA-Tencor is headquartered), proximity to Detroit Metropolitan Airport and other logistical advantages that support KLA-Tencor's leading international semiconductor and electronics customers," KLA Chief Strategic Officer Bobby Bell said in a news release in October.

KLA (NASDAQ: KLAC) announced a name change Jan. 10 to simplify its brand. It was founded in 1997 through the merger of KLA Instruments and Tencor Instruments.

KLA reported revenue of $1.1 billion in its fiscal 2019's third quarter, which ended March 31, up from $1.02 billion in the same quarter last year.