GT Advanced (GTAT) 10-Q 2009 Q4 Quarterly report

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Exhibit 32.2

CERTIFICATION PURSUANT TO
18 U.S.C. SECTION 1350,
AS ADOPTED PURSUANT TO
SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

        In connection with the Quarterly Report of GT Solar International, Inc. (the "Company") on Form 10-Q for the quarter ended December 26, 2009, as filed with the Securities and Exchange Commission (the "Report"), I, Richard E. Johnson, Principal Financial Officer of the Company, certify pursuant to 18 U.S.C. §1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that:

1.

The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2.

The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: February 5, 2010

/s/ RICHARD E. JOHNSON
Richard E. Johnson
Vice President of Finance and Corporate Controller
(Principal Financial and Accounting Officer)

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Exhibit 32.2