EXHIBIT 21.1

MATTSON TECHNOLOGY, INC.

SUBSIDIARIES OF THE REGISTRANT

Mattson International, Inc.

Mattson Technology Holdings, LLC

Mattson International Korea Co.

Mattson Technology Singapore Pte. Ltd.

Mattson International, Inc. Taiwan Branch *

Mattson Technology Holding GmbH

Mattson International GmbH

Mattson Thermal Products GmbH

Mattson International France Sarl

Mattson Trading (Shanghai) Co., Ltd.

Mattson Technology Cayman Holdings, Ltd.

Mattson Technology Canada, Inc.

Mattson Technology Israel Ltd.

* Note: this is not a subsidiary, but a branch registration