The final chips are rolling out of Micron Technology Inc.'s fabrication plant over the next few weeks, ending a nearly three-decade run that helped launch Micron into an international, multibillion-dollar powerhouse and put Boise on the global high-tech map.

Now, the Treasure Valley will have to cope with the loss of at least 3,500 Micron jobs in 10 months during one of the nation's worst economic crises.

Micron announced in February that it would lay off 2,000 people by August as it stops making its primary product, dynamic random-access memory chips, at its outdated Boise plant.

That announcement came on the heels of another Micron layoff of 1,400 to 1,600 employees announced in October.

After the layoffs, about 5,200 Idahoans will still be employed at Micron, down from more than 10,000 about four years ago.

Micron's slew of layoffs has knocked it from the top post as Idaho's largest private employer. St. Luke's Health System and Wal-Mart Stores now surpass it, with each employing about 7,500 employees in Idaho, according to the state Department of Labor.

Department representatives were at Micron on Tuesday and will return Thursday to offer advice on state employment services for laid-off workers, spokesman Bob Fick said. The agency has been sending staffers to Micron periodically since February to offer help to employees being laid off.

The state has provided training support for more than 730 ex-Micron workers and expects to serve more after this latest round of layoffs, Fick said.

The department received a $2 million federal emergency grant specifically to help laid-off Micron employees, he said. The state also has received about $4 million in federal trade adjustment assistance to provide job training to anyone who lost a job because of international trade competition. A lot of former Micron employees have enrolled, Fick said.

Micron is now one of the single largest contributors to the Treasure Valley's increasing unemployment rolls.

The number of unemployed workers in the Boise/Nampa area has increased by 11,000 since October 2008, according to the Labor Department, that's when Micron announced the first in a series of layoffs affecting at least 3,500 people, according to department filings.

The Treasure Valley's unemployment rate was 10.1 percent in June, up from 5.3 percent one year ago.

While Micron is phasing out most of its manufacturing operations in Boise, it plans to keep its research and development fabrication plant along with product design and support, quality control and corporate and general services offices in Boise, according to a company news release in February on the fab closure.

Micron did not return a phone call seeking comment.

Cynthia Sewell: 377-6428