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                                                                   EXHIBIT 10.15


NEITHER THIS NOTE NOR THE SHARES OF COMMON STOCK ISSUABLE UPON CONVERSION OF
THIS NOTE HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, OR THE
SECURITIES OR BLUE SKY LAWS OF CALIFORNIA OR ANY OTHER STATE AND MAY NOT BE
SOLD, PLEDGED, HYPOTHECATED, TRANSFERRED OR OTHERWISE DISPOSED OF IN THE ABSENCE
OF AN EFFECTIVE REGISTRATION STATEMENT FOR THE NOTE OR SHARES UNDER THE
SECURITIES ACT OF 1933, AND OTHER APPLICABLE SECURITIES OR BLUE SKY LAWS, OR AN
OPINION OF COUNSEL SATISFACTORY TO LIQUIDMETAL GOLF, THAT REGISTRATION IS NOT
REQUIRED UNDER SUCH ACT AND APPLICABLE STATUTES.

                          SUBORDINATED PROMISSORY NOTE

$1,500,000.00                                          Laguna Niguel, California
                                                               February 21, 2001



         FOR VALUE RECEIVED, LIQUIDMETAL TECHNOLOGIES, a California corporation
(the "Maker"), promises to pay to the order of JOHN KANG AND RICARDO A. SALAS,
or its successors or assigns (the "Holder") at 100 North Tampa Street, Suite
3150, Tampa, FL 33602 and 4300 West Cypress Street, Suite 900, Tampa, FL 33607,
respectively, or at such other place as the Holder may designate in writing from
time to time, in lawful money of the United States of America, the principal sum
of ONE MILLION FIVE HUNDRED THOUSAND DOLLARS ($1,500,000.00), together with
interest thereon as set forth below. As additional consideration therefor,
Holder shall receive warrants for the purchase of shares of common stock of the
Maker, as described in that certain Warrant, dated of even date herewith.

         1.       Payment of Interest.

                  a.       So long as there is no Event of Default, interest on
the unpaid principal balance under this Note shall accrue at the rate of seven
and one half percent (8.5%) per annum, beginning on February 22, 2001. If the
interest rate hereunder is determined by a court of competent jurisdiction to be
usurious or otherwise in violation of California law, the interest rate under
this Note shall equal the maximum interest rate allowable by California law. In
all cases, interest shall accrue during the actual number of days elapsed and
shall be computed on the basis of a 360-day year. This Note shall be paid and
converted as follows:


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                           i.       Payments of accrued but unpaid interest on
                  the outstanding principal balance under this Note shall be due
                  and payable upon scheduled maturity on December 31, 2002,
                  unless such day is not a business day, in which case payment
                  shall be due on the first Business Day after such day (an
                  "Interest Payment Date");

                  b.       The Maker shall be liable for all fees and expenses
arising from the interpretation or enforcement of this Note, or from the
collection of amounts due hereunder, including but not limited to reasonable
legal fees and expenses (collectively, the "Additional Amounts").

        2.       Subordination. THE RIGHTS OF THE HOLDER OF THIS NOTE TO RECEIVE
PAYMENT OF ANY PRINCIPAL HEREOF OR INTEREST HEREON IS SUBJECT AND SUBORDINATE TO
THE PRIOR PAYMENT OF THE PRINCIPAL OF AND INTEREST ON ALL OTHER INDEBTEDNESS OF
THE MAKER, WHETHER NOW OUTSTANDING OR SUBSEQUENTLY INCURRED, WHETHER SECURED OR
UNSECURED, AND ANY DEFERRALS, RENEWALS OR EXTENSIONS OF SUCH INDEBTEDNESS OR ANY
DEBENTURES, BONDS OR NOTES EVIDENCING SUCH INDEBTEDNESS (THE "SENIOR
INDEBTEDNESS"). UPON ANY RECEIVERSHIP, INSOLVENCY, ASSIGNMENT FOR THE BENEFIT OF
CREDITORS, BANKRUPTCY, REORGANIZATION, SALE OF ALL OR SUBSTANTIALLY ALL OF THE
ASSETS AND LIABILITIES OF THE MAKER, OR IN THE EVENT THIS NOTE IS DECLARED DUE
AND PAYABLE UPON THE OCCURRENCE OF AN EVENT OF DEFAULT, THEN NO AMOUNT SHALL BE
PAID BY THE MAKER WITH RESPECT TO PRINCIPAL AND INTEREST HEREON UNLESS AND UNTIL
THE PRINCIPAL OF, AND INTEREST ON, ALL SENIOR INDEBTEDNESS THEN OUTSTANDING IS
PAID IN FULL.

        3.       Prepayments. The Maker may elect to repay the entire principal
amount and all interest due thereon on or before the scheduled maturity date on
December 31, 2002. The Maker shall provide written notice to the Holder of its
intent to repay to the Holder at least three (3) days prior to the date on which
the Maker intends to repay the obligation.

        4.       Events of Default. The occurrence of any of the following
events shall constitute an "Event of Default" under this Note:

                a.       any failure by the Maker to pay principal, accrued but
unpaid interest or other amounts when due under this Note, unless such failure
is cured in full within ten (10) Business Days after receiving written notice
informing the Maker of such failure;

                 b.       any material breach, violation or default (including
but not limited to technical and non-monetary defaults) by the Maker with
respect to any of its other covenants,


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obligations or duties under this Note, unless such breach, violation or default
is cured in full within sixty (60) Business Days after receiving written notice
informing the Maker of such breach, violation or default;

                 c.       the filing against the Maker of any bankruptcy
petition that is not dismissed within ninety (90) days after filing or the
filing by or on behalf of the Maker of any bankruptcy petition;

                 d.       the appointment of receiver, custodian or trustee to
operate or manage the Maker or substantially all of its assets or businesses;

                 e.       the entry of any un-appealed, non-appealable or
otherwise final judgment, or series of such judgments within any twelve-month
period, against the Maker in an amount, or in an aggregate amount, of $500,000
or more, unless such judgment (or each judgment in such series) is satisfied in
full within thirty (30) days after entry without causing an Event of Default;

                 f.       the dissolution or liquidation of the Maker; or

                 g.       any merger involving, consolidation involving, sale of
all or substantially all assets by, or share exchange by, the Maker, except in
connection with an IPO by the Maker.

         5.       Rights Remedies and Waivers. The Holder shall have all rights
and remedies available at law, in equity or by constitution, statute, rule,
regulation or ordinance, including but not limited to rights and remedies
granted in this Note with respect to any Event of Default.

         Without limiting the generality of the foregoing provisions of this
Section, the Holder shall have the right, upon any Event of Default, to declare
the entire principal balance and accrued but unpaid interest due from the Maker
to be immediately due and payable in full. The Maker shall be liable for
Additional Amounts, as defined in Section 1.b. of this Note.

         In no event shall a waiver of rights or remedies arise solely from the
oral representations of the Holder or from any delay by it in exercising, or any
past failures to exercise, rights or remedies. A waiver of rights and remedies
by the Holder shall not be effective or binding unless, and then only to the
extent that, such waiver appears in this Note, or the Holder signs an express
written waiver of rights or remedies and causes such written waiver to be
delivered to the Maker.

         The Maker, to the maximum extent permitted by law, hereby waives each
of the following: (a) the benefit of, and the right to assert, any statute of
limitations defenses affecting the Maker's rights, duties or obligations under
this Note; (b) presentation, demand, protest, notices of dishonor and protest
and the benefits of homestead exemptions; and (c) all defenses and pleas with
respect to any extensions of the time for payment under this Note, except as may


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be granted expressly by the Holder, in its sole discretion, in a written
instrument signed by the Holder and delivered to the Maker.

         6.       Governing Law. The Holder shall be entitled to have all of its
claims, causes of action, suits, demands, counterclaims and defenses under this
Note interpreted and enforced in accordance with the laws of the State of
California, without regard to any conflicts of law provisions or principles
thereof to the contrary.

         7.       Modification. This Note shall not be modified unless, and then
only to the extent that, a written modification is executed by the Holder and
the Maker, or its respective successors and assigns.

         8.       Assignment. The Maker shall not assign or delegate, whether in
whole or in part, any of its rights, duties or obligations under this Note, and
any attempted assignment or delegation in violation of this Note shall be void.

         9.       Severable Provisions. All provisions in this Note are
severable and each valid and enforceable provision shall remain in full force
and effect, regardless of any determination that is binding upon the parties
hereto and that renders other provisions of this Note invalid or unenforceable
To the extent, if any, that a court of competent jurisdiction determines that
certain provisions of this Note are invalid or unenforceable, the Maker and the
Holder hereby authorize such court to modify such provisions, in a manner
consistent with the intent of the Maker and the Holder, as such court deems
reasonably necessary to make such provisions valid and enforceable.

         10.      Terms of Convenience. References to this Note mean this
Convertible Subordinated Promissory Note, as it may be amended or replaced from
time to time. Terms such as "hereof," "herein," "hereto," "hereby," "hereunder"
and similar references to this Note shall be deemed to refer to this Note as a
whole and not to any particular section or provision of this Note. Captions and
headings are used in this Note for convenience only and shall not be construed
to affect the meaning of this Note.

         IN WITNESS WHEREOF, this Convertible Subordinated Promissory Note has
been executed as of the first date written above.


         MAKER:                          LIQUIDMETAL TECHNOLOGIES,
                                         a California corporation


                                         By: /s/ James Kang
                                             -----------------------------------
                                             James Kang,
                                             Chief Executive Officer


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