EXHIBIT 10.19



                                 PROMISSORY NOTE

$3,000,000                                                  Somerset, New Jersey
                                                               February 22, 2001


     FOR  VALUE  RECEIVED,  the  undersigned,   Reuben  F.  Richards,  Jr.  (the
"Borrower"),  hereby  promises  to pay to the order of EMCORE  Corporation  (the
"Company"),  in lawful  money of the United  States of  America  in  immediately
available funds, at its offices at 145 Belmont Drive, Somerset, New Jersey 08873
(or such other place as Company may direct) the  principal  sum of THREE MILLION
DOLLARS AND NO CENTS  ($3,000,000.00).  Principal and accrued  interest shall be
payable on February 22, 2004 (the "Maturity Date") at the foregoing address.

     1. Interest.  Interest shall accrue on the unpaid principal balance of this
Note at a rate of  5.18%  per  annum,  compounded  annually.  Interest  shall be
payable on the Maturity Date.

     2. Limited  Recourse.  The Company's  recourse in respect of the Borrower's
obligations  under this Note shall be limited to the  Collateral  (as defined in
the Pledge Agreement,  dated as of the date hereof,  between the Company and the
Borrower (the "Pledge Agreement")).

     3. Security.  All  obligations of Borrower under this Note are secured by a
pledge of certain shares of EMCORE  Corporation  common stock  ("Common  Stock")
pursuant to the Pledge  Agreement.  By executing this Note, the Borrower  hereby
agrees to execute such other  instruments  as the Company may direct in order to
evidence and perfect Company's  security interest in such Common Stock (together
with the Pledge Agreement, the "Pledge Documents").

     4. Covenant of the Borrower. Upon receipt of the proceeds of this Note, the
Borrower  shall  apply all such  proceeds  towards  the  purchase  of a personal
residence.

     5. Voluntary  Prepayments.  The Borrower may, at his option,  prepay at any
time all or any portion of the principal  amount of this Note then  outstanding,
together with all accrued  interest thereon through the date of such prepayment,
without premium or penalty.

     6. Acceleration.

     (a) If the Borrower voluntarily  terminates his employment with the Company
for any reason or if the Company  terminates the Borrower's  employment  without
cause, the Company shall have the right to accelerate all or part of the amounts
outstanding  under this Note.  If the  Borrower  is  terminated  for cause,  all
principal and interest outstanding under this Note will automatically become due


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and payable  sixty (60) calendar days after the  termination  of the  Borrower's
service with the Company.

     (b) The  Company  will  have the  right to  accelerate  the  principal  and
interest due under this Note upon the  occurrence of the following  events:  (i)
there is default under, or a breach of, any covenant, representation or warranty
of the  Borrower  under this Note or the  Pledge  Documents,  (ii) the  Borrower
applies for or consents to the appointment of a receiver,  trustee, custodian or
liquidator  of any of his  property,  admits in writing his inability to pay his
debts as they mature,  makes a general  assignment as a bankrupt or insolvent or
is the  subject of an order for  relief  under  Chapter 13 of the United  States
Bankruptcy  Code or files a voluntary  petition in  bankruptcy  or a petition or
answer  seeking  an  arrangement  with  creditors  or to take  advantage  of any
bankruptcy,  insolvency,  readjustment or debt or liquidation law or statute, or
an answer admitting the material  allegations of a petition filed against him in
any  proceeding  under  any such law or (iii) an  order,  judgment  or decree is
entered  by any  court  of  competent  jurisdiction,  without  the  application,
approval or consent of the Borrower, approving a petition appointing a receiver,
trustee,  custodian or liquidator of all or a substantial  part of the assets of
the Borrower and such order, judgment or decree continues unstayed and in effect
for a period of thirty (30) days; provided that if an event specified in (ii) or
(iii) above shall occur, all principal and interest  outstanding under this Note
shall become automatically due and payable.


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     7. Notices. All notices and other  communications  required or permitted to
be given  hereunder  shall be in  writing  and shall be deemed to have been duly
given  if  delivered  personally  or  sent by  certified  mail,  return  receipt
requested,  first-class  postage  prepaid  to the below  listed  parties  at the
following addresses:

                If to the Company, to:

                EMCORE Corporation
                145 Belmont Drive
                Somerset, NJ  08873
                Attention:   CFO

     If to the Borrower, at the address set forth at the end of this Note, or to
such other  address as either party shall have last  designated by notice to the
other party.  All such notices and  communications  shall be deemed to have been
received on the earlier of the date of receipt and the third  business day after
the date of mailing thereof.

     8.  Amendments.  No  amendment  of this Note shall be  effective  unless in
writing and signed by the Borrower and the Company.

     9. Waiver.  The  Borrower,  for himself and his legal  representatives  and
successors,  hereby expressly waives presentment,  demand, notice,  protest, and
all other  demands or  notices  in  connection  with the  delivery,  acceptance,
endorsement, performance, default, or enforcement of this Note.

     10. No Set-Off. This Note is not subject to set-off by the Borrower for any
amounts for any reason.

     11.  Effect of Delay or  Omission.  No delay or  omission of the Company in
exercising any right or remedy  hereunder shall  constitute a waiver of any such
right or remedy.

     12. Costs of  Collection.  The Borrower  will pay all costs and expenses of
collection,  including  reasonable  attorneys'  fees,  incurred  or  paid by the
Company in  enforcing  this Note or the  obligations  hereby  evidenced,  to the
extent permitted by law.

     13.  Governing Law. This Note shall be construed and enforced in accordance
with the laws of the State of New Jersey, without regard to any conflict of laws
rules.

     14. Headings. The section and paragraph headings hereof are for convenience
of  reference  only and shall not be deemed to construe or affect the meaning of
any of the provisions hereof.


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     IN WITNESS  WHEREOF,  the Borrower  has  executed  this Note as of the date
first above written,  and by such execution  acknowledges each of the provisions
of this Note.

                                    /s/ Reuben F. Richards, Jr.
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                                        Reuben F. Richards, Jr.

                                    Address:

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