Andover, MA-MKS Instruments, Inc., a leading supplier of gas measurement, control and analysis products used in semiconductor and other advanced thin-film manufacturing processes, announced today that it has completed its previously announced acquisition of Spectra International, a privately held company with products and technology in process monitoring. The transaction was for $9.7 million in cash; 183,293 shares of MKS common stock; fully vested options to purchase 83,679 shares of common stock per share of Spectra common stock; and the assumption of approximately $1 million in long-term debt. The transaction also includes contingent earnout payments of up to $12 million. The acquisition is subject to customary closing conditions. Spectra based in Morgan Hill, CA, designs and manufactures mass spectrometer and optical spectrometer based process monitoring products used in the semiconductor, thin-film coatings and advanced material processing industries. It has manufacturing operations in California and the UK with a total of 70 employees worldwide.