CUPERTINO, California ( TheStreet) -- Verigy ( VRGY) , a semiconductor testing company, agreed to buy rival LTX-Credence ( LTXC). Under the terms of the agreement, Verigy and LTX-Credence will become subsidiaries of Holdco, a newly created subsidiary, or LTX-Credence would become a unit of Verigy. LTX-Credence shareholders will receive a fixed exchange ratio of 0.96 a share of Verigy stock. The deal is valued at roughly between $420 million to $440 million. "By joining forces, we expect the combined scale to strengthen our global presence" for semiconductor test systems, Verigy said in a statement Thursday. Verigy shares closed Wednesday at $8.91; LTX-Credence shares finished at $5.98. The companies expect the merger to close in the first half of 2011. -- Written by Joseph Woelfel >To contact the writer of this article, click here: Joseph Woelfel >To submit a news tip, send an email to: email@example.com.