EXHIBIT 10(aa)
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                        FIRST LOAN MODIFICATION AGREEMENT

         This First Loan Modification Agreement (this "Loan Modification
Agreement") is entered into as of March 31, 2008, by and between (i) SILICON
VALLEY BANK, a California-chartered bank, with its principal place of business
at 3003 Tasman Drive, Santa Clara, California 95054 and with a loan production
office located at One Newton Executive Park, Suite 200, 2221 Washington Street,
Newton, Massachusetts 02462 ("Bank") and (ii) SPIRE CORPORATION ("Spire"), a
Massachusetts corporation, and SPIRE SEMICONDUCTOR, LLC, f/k/a BANDWITH
SEMICONDUCTOR, LLC ("Semiconductor"), a Delaware limited liability company
(Spire and Semiconductor, are referred to herein, individually, jointly,
severally and collectively, as the "Borrower").

1.       DESCRIPTION OF EXISTING INDEBTEDNESS AND OBLIGATIONS. Among other
indebtedness and obligations which may be owing by Borrower to Bank, Borrower is
indebted to Bank pursuant to a loan arrangement dated as of May 25, 2007,
evidenced by, among other documents, a certain Loan and Security Agreement dated
as of May 25, 2007, between Borrower and Bank (as amended, the "Loan
Agreement"). Capitalized terms used but not otherwise defined herein shall have
the same meaning as in the Loan Agreement.

2.       DESCRIPTION OF COLLATERAL. Repayment of the Obligations is secured by
the Collateral as described in the Loan Agreement (together with any other
collateral security granted to Bank, the "Security Documents").

Hereinafter, the Security Documents, together with all other documents
evidencing or securing the Obligations shall be referred to as the "Existing
Loan Documents".

3.       DESCRIPTION OF CHANGE IN TERMS.

         A.  Modifications to Loan Agreement.

             1   The Loan Agreement shall be amended by deleting the following
                 provision appearing as Section 2.2(a) thereof:

                 "   (a) Interest Rate. Subject to Section 2.2(b), the principal
                 amount outstanding for each Equipment Advance shall accrue
                 interest at a floating per annum rate equal to one half of one
                 percentage point (0.5%) above the Prime Rate, which interest
                 shall be payable monthly."

                 and inserting in lieu thereof the following:

                 "   (a) Interest Rate. Subject to Section 2.2(b), the principal
                 amount outstanding for each Equipment Advance shall accrue
                 interest at a floating per annum rate equal to one half of one
                 percentage point (0.5%) above the Prime Rate, which interest
                 shall be payable monthly. Commencing on the 2008 Closing Date,
                 and subject to Section 2.2(b), the principal amount outstanding
                 for each Equipment Advance shall accrue interest at a floating
                 per annum rate equal to one percentage point (1.0%) above the
                 Prime Rate, which interest shall be payable monthly."

             2   The Loan Agreement shall be amended by deleting the following
                 provision appearing as Section 6.7 entitled "Financial
                 Covenants":

                 "6.7 Financial Covenants.
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                     Borrower shall maintain, at all times, to be tested as of
                 the last day of each month, unless otherwise noted, on a
                 consolidated basis:

                     (a) Adjusted Quick Ratio. An Adjusted Quick Ratio of at
                 least: (i) 1.0 to 1.0 as of the last day of each of the months
                 ending May 31, 2007, and June 30, 2007; and (ii) 1.5 to 1.0 as
                 of the last day of the month ending July 31, 2007, and as of
                 the last day of each month thereafter. Notwithstanding the
                 foregoing, the failure of Borrower to comply with this
                 financial covenant during any such month shall not constitute
                 an Event of Default provided that: (a) during any quarter in
                 which Borrower maintains Net Income (tested as of the last day
                 of each quarter) of less then One Dollar ($1.00), Borrower's
                 Unrestricted Cash is greater than or equal to one and
                 one-quarter times (1.25x) the outstanding principal amount of
                 the Equipment Line at all times during such month, or (b)
                 during any quarter in which Borrower maintains Net Income
                 (tested as of the last day of each quarter) of at least One
                 Dollar ($1.00), Borrower's Unrestricted Cash is greater than or
                 equal to one times (1.0x) the principal amount of the
                 outstanding Equipment Line at all times during such month.

                     (b) Minimum Quarterly Net Income. Borrower shall maintain
                 Net Income of at least: (i) ($1,500,000.00) as of the last day
                 of the quarter ending June 30, 2007, (ii) $1.00 as of the last
                 day of the quarter ending September 30, 2007, and (iii)
                 $250,000.00 as of the last day of the quarter ending December
                 31, 2007, and as of the last day of each quarter thereafter."

                 and inserting in lieu thereof the following:

                 "6.7 Financial Covenants.

                     Borrower shall maintain at all times, to be tested as of
                 the last day of each month, unless otherwise noted, on a
                 consolidated basis with respect to Borrower and its
                 Subsidiaries:

                     (a) Liquidity. The ratio of (x) (i) Borrower's unrestricted
                 cash and Cash Equivalents at Bank plus (ii) eighty percent
                 (80%) of Eligible Accounts (as defined in the Revolving Line
                 Loan Agreement) plus (iii) the lesser of (1) twenty-five
                 percent (25%) of Borrower's Eligible Inventory (as defined in
                 the Revolving Line Loan Agreement) or (2) $2,500,000 to (y) all
                 outstanding Credit Extensions, including reserves, shall be
                 greater than 2.00:1.00; and

                     (b) Profitability. A minimum Net Income, on a trailing six
                 (6) month basis, of (i) not less than ($1,000,000), for each
                 monthly period beginning on the Effective Date through and
                 including May 31, 2008; and (ii) not less than $1.00, for each
                 monthly period beginning June 1, 2008 and thereafter."

             3   The Loan Agreement shall be amended by inserting the following
                 new provision to appear as Section 8.10 thereof:

                 "8.10 Revolving Line Loan Agreement. An Event of Default (as
                 such term is defined under the Revolving Line Loan Agreement)
                 occurs under the Revolving Line Loan Agreement."

             4   The Loan Agreement shall be amended by inserting the following
                 new definitions to appear alphabetically in Section 13.1
                 thereof:

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                 "   "2008 Closing Date" is March 31, 2008.

                     "Net Income" means, as calculated on a consolidated basis
                     for Borrower and its Subsidiaries for any period as at any
                     date of determination, the net profit (or loss), after
                     provision for taxes, of Borrower and its Subsidiaries for
                     such period taken as a single accounting period.

                     "Revolving Line Loan Agreement" is that certain Loan and
                     Security Agreement by and between Borrower and Bank as of
                     the 2008 Closing Date, as may be amended from time to
                     time."

             5   The Loan Agreement shall be amended by deleting the following
                 subsection (d) of the definition of "Permitted Investments"
                 appearing in Section 13.1 thereof:

                 "   (d) Investments of Subsidiaries in or to other
                 Subsidiaries or Borrower and Investments by Borrower in
                 Subsidiaries not to exceed One Hundred Thousand Dollars
                 ($100,000) in the aggregate in any fiscal year;"

                 and inserting in lieu thereof:

                 "   (d) Investments of Subsidiaries in or to other
                 Subsidiaries or Borrower and Investments by Borrower in
                 Subsidiaries (with the exception of Gloria Spire Solar, LLC)
                 not to exceed One Hundred Thousand Dollars ($100,000) in the
                 aggregate in any fiscal year;"

             6   The Loan Agreement shall be amended by deleting the following
                 definition appearing in Section 13.1 thereof:

                 ""Prime Rate" is Bank's most recently announced "prime rate,"
                 even if it is not Bank's lowest rate.

                 and inserting in lieu the following:

                 ""Prime Rate" is the greater of (i) six percent (6.0%), and
                 (ii) Bank's most recently announced "prime rate," even if it is
                 not Bank's lowest rate.

             7   The Compliance Certificate appearing as Exhibit C to the Loan
                 Agreement is hereby replaced with the Compliance Certificate
                 attached as Exhibit A hereto.

         B.  Waivers.

             1   Bank hereby waives Borrower's existing defaults under the Loan
                 Agreement by virtue of Borrower's failure to comply with the:
                 (i) Adjusted Quick Ratio financial covenant set forth in
                 Section 6.7(a) thereof as of the months ended November 30,
                 2007, December 31, 2007, January 31, 2008, and February 29,
                 2008 (required prior to this Loan Modification Agreement), and
                 (ii) Minimum Quarterly Net Income financial covenant set forth
                 in Section 6.7(b) as of the month ended December 31, 2007
                 (required prior to this Loan Modification Agreement). Bank's
                 waiver of Borrower's compliance of said affirmative covenants
                 shall apply only to the foregoing specific periods.

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4.       FEES. Borrower shall pay to Bank a modification fee equal to Ten
Thousand Dollars ($10,000), which fee shall be due on the date hereof and shall
be deemed fully earned as of the date hereof. Borrower shall also reimburse Bank
for all reasonable legal fees and expenses incurred in connection with this
amendment to the Existing Loan Documents.

5.       CONSISTENT CHANGES. The Existing Loan Documents are hereby amended
wherever necessary to reflect the changes described above.

6.       RATIFICATION OF LOAN DOCUMENTS. Borrower hereby ratifies, confirms, and
reaffirms all terms and conditions of all security or other collateral granted
to the Bank, and confirms that the indebtedness secured thereby includes,
without limitation, the Obligations.

7.       NO DEFENSES OF BORROWER. Borrower hereby acknowledges and agrees that
Borrower has no offsets, defenses, claims, or counterclaims against Bank with
respect to the Obligations, or otherwise, and that if Borrower now has, or ever
did have, any offsets, defenses, claims, or counterclaims against Bank, whether
known or unknown, at law or in equity, all of them are hereby expressly WAIVED
and Borrower hereby RELEASES Bank from any liability thereunder.

8.       CONTINUING VALIDITY. Borrower understands and agrees that in modifying
the existing Obligations, Bank is relying upon Borrower's representations,
warranties, and agreements, as set forth in the Existing Loan Documents. Except
as expressly modified pursuant to this Loan Modification Agreement, the terms of
the Existing Loan Documents remain unchanged and in full force and effect.
Bank's agreement to modifications to the existing Obligations pursuant to this
Loan Modification Agreement in no way shall obligate Bank to make any future
modifications to the Obligations. Nothing in this Loan Modification Agreement
shall constitute a satisfaction of the Obligations. It is the intention of Bank
and Borrower to retain as liable parties all makers of Existing Loan Documents,
unless the party is expressly released by Bank in writing. No maker will be
released by virtue of this Loan Modification Agreement.

9.       COUNTERSIGNATURE. This Loan Modification Agreement shall become
effective only when it shall have been executed by Borrower and Bank.


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         This Loan Modification Agreement is executed as a sealed instrument
under the laws of the Commonwealth of Massachusetts as of the date first written
above.


BORROWER:                                     BANK:

SPIRE CORPORATION                             SILICON VALLEY BANK

By:      /s/ Roger G. Little                  By:      /s/ Karen Dunn
         -----------------------------                 -------------------------
Name:    Roger G. Little                      Name:    Karen Dunn
Title:   Chief Executive Officer              Title:   Relationship Manager



By:      /s/ Christian Dufresne
         -----------------------------
Name:    Christian Dufresne
Title:   Chief Financial Officer



SPIRE SEMICONDUCTOR, LLC, f/k/a
BANDWITH SEMICONDUCTOR, LLC

By:      /s/ Roger G. Little
         -----------------------------
Name:    Roger G. Little
Title:   Chief Executive Officer



By:      /s/ Christian Dufresne
         -----------------------------
Name:    Christian Dufresne
Title:   Chief Financial Officer




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