Amazon is opening a 1 million-square-foot fulfillment center in Middletown, Delaware, which is the e-commerce giant’s second facility in the state. Amazon says that the new center will create 850 full-time jobs, and will cost $90 million.

Amazon’s fulfillment centers enables the company and third-party merchants to store inventory and fulfill orders. The Middletown center joins Amazon’s New Castle fulfillment facility, which was opened in 1997. Amazon says that the New Castle center currently employs “hundreds of full-time workers,” but it sounds like the new facility will be larger. The Middletown facility is expected to be complete this fall.

In December, the Delaware Economic Development Office awarded the company $3.47 million from the Delaware Strategic Fund to support the expansion, of which $2.12 million will help create new jobs at the site. The fund will also contribute to the company’s infrastructure investment, equal to 3 percent of the total capital expenditures, or a maximum of $1.35 million. A separate grant for up to $4 million from the Delaware New Jobs Infrastructure Fund will be used to build extensions of public roads to serve the project, improve traffic flow and provide access to additional properties for future economic development. Amazon will also benefit from a real estate tax abatement from the town of Middletown for the next 10 years.

Amazon has been ramping up the development of its fulfillment centers over the past year. In 2011, the e-commerce company opened 15 new centers worldwide. As of last July, Amazon had roughly 65 centers worldwide. And this year, the company opened a new center in India and in South Carolina.