Exhibit 10.22

JOINDER AND AMENDMENT AGREEMENT TO

THE JOINT VENTURE AGREEMENT

THIS JOINDER AND AMENDMENT AGREEMENT (this “Agreement”) to that certain Joint Venture Agreement, dated as of February 10, 2011 (the “Joint Venture Agreement”), in relation to SMP Ltd., a company organized under the laws of Korea (“SMP”), by and between SunEdison Products Singapore Pte. Ltd. (formerly known as MEMC Singapore Pte. Ltd.), a company organized and existing under the laws of Singapore (“SunEdison Singapore”), and Samsung Fine Chemicals Co., Ltd., a company organized and existing under the laws of Korea (“SFC”), is entered into as of [•], 2014. SunEdison Singapore, SSBV (as defined below) and SFC are sometimes referred to herein as the “Parties” and each individually as a “Party”. Capitalized terms not defined herein have the meanings set forth in the Joint Venture Agreement.

R E C I T A L S

WHEREAS, pursuant that certain share purchase agreement, dated as of March 20, 2014, by and between SunEdison, Inc., a corporation organized under the laws of the State of Delaware (“SunEdison”), and SFC, as of the date hereof, SunEdison is acquiring from SFC certain number of ordinary shares of SMP (the “SMP Transaction”);

WHEREAS, in connection with the SMP Transaction, SunEdison shall concurrently enter into, and cause to be entered, certain contribution agreements whereby the ordinary shares of SMP acquired from SFC shall be ultimately owned by SunEdison Semiconductor B.V., a private company with limited liability incorporated under the laws of the Netherlands and having its office address at Naritaweg 165, 1043 BW Amsterdam, the Netherlands (“SSBV”), as of the date hereof;

WHEREAS, after the above-described transactions have been consummated, the respective percentage ownership of each of the Parties in SMP shall be as follows: SunEdison Singapore – 50%; SSBV – 35%; and SFC – 15%;

WHEREAS, in connection with the SMP Transaction, the Parties desire SSBV to become a party to the Joint Venture Agreement;

WHEREAS, Section 18.7 of the Joint Venture Agreement provides that no amendment or change thereof or addition thereto shall be effective or binding on the Parties unless reduced to writing and executed by the duly authorized representatives of the Parties; and

WHEREAS, pursuant to Section 18.7 of the Joint Venture Agreement, the Parties now desire to amend the Joint Venture Agreement, with such amendment being effective as of the date of this Agreement.

NOW, THEREFORE, in consideration of the promises and the mutual agreements herein set forth, the Parties hereby agree as follows:

A G R E E M E N T

“7.2 Statutory Auditors. The Company shall have at least one (1) Statutory Auditor. For so long as SFC shall have no less than ten percent (10%), it shall have the right to nominate one (1) Statutory Auditor for election at the General Meeting of Shareholders, and the other Party shall exercise its voting rights so that the nominee of such Party shall be elected as Statutory Auditor. Initially, the Company shall have two (2) Statutory Auditors and each of SunEdison Singapore and SFC shall be entitled to nominate one (1) Statutory Auditor. Each Party entitled to nominate a Statutory Auditor shall consult in good faith with the other Party prior to making such nomination. The provisions of Section 6.2(c), (d) and (e) shall apply to the Statutory Auditors, mutatis mutandis.”

“7.3 Other Officers. The Company shall also have the following officers: (i) chief financial officer; (ii) vice president for technology; (iii) vice president for human resources, relationship management and general affairs (which three officers are referred to herein collectively as the “Senior Officers” and individually as a “Senior Officer”); and (iv) such other officers as may be necessary for the operation of the Company. The Senior Officers shall be appointed and removed by the Board and other officers shall be appointed and removed by the Representative Director. For so

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long as SFC holds any Shares, SFC shall have the right to nominate the vice president for human resources, relationship management and general affairs for appointment by the Board, and MEMC Singapore shall procure for its nominated Directors to exercise voting rights so that such nominee of SFC shall be appointed as vice president for human resources, relationship management and general affairs. For so long as MEMC Singapore’s Shareholding is no less than fifty percent (50%), MEMC Singapore shall have the right to nominate the chief financial officer and the vice president for technology for appointment by the Board, and SFC shall procure for its nominated Directors to exercise voting rights so that such nominees of MEMC Singapore shall be appointed as chief financial officer and vice president for technology, respectively. Each Party entitled to nominate any Senior Officer shall consult in good faith with the other Party prior to making such nomination, although the final decision to appoint such Senior Officer shall ultimately reside with such Party. The provisions of Section 6.2(c) and (d) shall apply to the Senior Officers, mutatis mutandis.”

“8.3 Quorum and Voting Requirements. Except to the extent otherwise required by mandatory provisions of applicable law, any resolution or action at a General Meeting of Shareholders shall require an affirmative vote of a majority of the Shares represented (whether in person or by proxy) at such meeting where a majority of the total issued and outstanding Shares are represented in person or by proxy; provided, however, that any resolution or action with respect to the matters listed in Schedule I hereto shall require an affirmative vote of at least ninety percent (90%) of the total issued and outstanding Shares of the Company at a General Meeting of Shareholders.”

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[Signature Pages Follow]

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IN WITNESS WHEREOF, the Parties have caused this Agreement to be executed by their respective authorized officers as of the date aforesaid.

[Signature Page to Joinder and Amendment Agreement to Joint Venture Agreement]

[Signature Page to Joinder and Amendment Agreement to Joint Venture Agreement]

[Signature Page to Joinder and Amendment Agreement to Joint Venture Agreement]

EXHIBIT A

SCHEDULE I

Matters Requiring Super-Majority Vote of General Meeting of Shareholders