Intel forecasts its huge new Hillsboro factory will increase the company’s Oregon workforce by about 9 percent, 1,750 more jobs in total, according to permitting documents submitted to city planners.

The chipmaker is already the state’s largest corporate employer. The additional jobs would bring its Oregon workforce near 22,000.

Intel has declined to discuss details of its project but confirmed its plans last week to its Hillsboro neighbors. The new facility will adjoin two existing factories known collectively as D1X.

Intel hasn’t disclosed a price tag for the work. But new chip factories, known in the industry as fabs, run several billions of dollars apiece. The work will surely be among the largest capital projects in Oregon history.

This third phase of D1X, called Mod3, will be 1.5 million square feet, according to permitting documents Hillsboro released in response to a public records request.

That’s slightly larger than each of the first two phases and will increase D1X by 60 percent altogether, to just under 4 million square feet. The three phases will be interconnected but will have independent mechanical and electrical systems.

Additionally, Intel said it plans a six-story, 1 million square foot support structure with utility services and 2,200 parking spaces.

Christian Dieseldorff, principal analyst for the industry trade group SEMI, said a fab of the size Intel is seeking would cost between $4 billion and $5 billion. Construction cost represents up to a quarter of that, he said. The remainder would be spent equipping the facility.

Even at this scale, Dieseldorff said D1X will be smaller than contemporary high-volume production fabs and is better suited for research and pilot lines. That’s in keeping with past practice: Intel develops each new class of microprocessor in Oregon, then duplicates the manufacturing process in fabs around the world.

Headcount and Ronler Acres would grow to 16,186 by the end of 2021, according to the permitting documents, up from 14,438 currently. Intel says it expects to add 1,571 regular “blue badge” employees and 177 contract workers (who carry Intel-issued green badges.)

The company hasn’t said when it will start production but the permitting documents suggest Intel expects to have the new fab operating by the end of 2021, just under three years from now.

Intel said last year it planned manufacturing expansion in Oregon, Ireland and Israel to increase its production capacity. The company suffered a major shortfall in supply last year after unexpected demand for PCs, coupled with delays to its new class of 10-nanometer microprocessor, left it without the capacity to fill requests for its existing 14nm processor.

The new fabs are also designed to accommodate a big new manufacturing tool for extreme ultraviolet lithography, or EUV. EUV tools, the size of a bus, cannot operate in older fabs but will be necessary to make Intel’s forthcoming 7nm chips, due sometime in the next several years.

Intel spends billions of dollars a year to equip its factories with the latest production technology. Oregon exempts Intel’s equipment from the property taxes other businesses pay, a tax break worth nearly $200 million to the company last year alone.

The value of those exemptions will increase dramatically as Intel expands; how much it will save depends on how much it spends.

-- Mike Rogoway | twitter: @rogoway | 503-294-7699