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                                                                     EXHIBIT 5.2


                [Winthrop, Stimson, Putnam & Roberts Letterhead]

                                October 29, 1997


Lam Research Corporation
4650 Cushing Parkway
Fremont, CA  94538

        Re:    Registration Statement on Form S-3 of Lam Research Corporation

Ladies and Gentlemen:

        We are acting as special New York counsel for Lam Research Corporation,
a Delaware corporation (the "Company"), in connection with the registration
under the Securities Act of 1933 (the "Act"), of up to $310,000,000 of the
Company's 5% Convertible Subordinated Notes due 2002 (the "Notes") and 3,531,958
shares of the company's Common Stock, par value $.001 per share, issuable on
conversion thereof (the "Shares"), to be sold from time to time by the selling
securityholders listed in a Registration Statement on Form S-3, which is
expected to be filed with the Securities and Exchange Commission (the
"Commission") on or about the date hereof (as amended, the "Registration
Statement").

        In reaching the conclusions expressed in this opinion we have examined
and relied on such documents, corporate records and other instruments, including
the Indenture (the "Indenture") dated as of August 15, 1997 between the Company
and LaSalle National Bank (the "Trustee")and made such further investigation and
inquiry as we have deemed necessary to reach the opinions expressed herein. We
have not examined the Notes, except specimens thereof. In making the foregoing
examination, we have assumed the genuineness of all signatures on original
documents of all copies submitted to us.

        Based solely upon the foregoing, subject to the qualifications and
exceptions hereinafter stated, it is our opinion that, assuming (i) that the
Company has sufficient legal capacity under the laws of its jurisdiction of
incorporation to enter into and carry out its obligations under the Indenture
and the Notes; (ii) assuming the due authorization and execution and delivery by
the Company in accordance with such authorization and as contemplated by the
form of such agreement of the Indenture; (iii) assuming the due authorization
and execution and delivery by the Company in accordance with such authorization
of the Notes and (iv) assuming due authorization, execution and delivery by the
Trustee of the Indenture, (x) the Indenture is a valid and binding obligation of
the Company, enforceable against the Company in accordance with the terms
thereof, except as (i) limited or otherwise affected by applicable bankruptcy,
insolvency, reorganization, moratorium, fraudulent transfer and other similar 
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Lam Research Corporation
October 24, 1997
Page 2


laws of general application relating to or affecting creditor's rights and (ii)
limited by general principles of equity (regardless of whether considered in a
proceeding at law or in equity) including, without limitation, the availability
or unavailability of equitable remedies and an implied covenant of good faith
and fair dealing and (y) the Notes, assuming they have been executed by the
Company and authorized by the Trustee in accordance with the provisions of the
Indenture and delivered to and paid for by the initial purchasers thereof,
constitute valid and legally binding obligations of the Company, enforceable
against the Company in accordance with the terms thereof except as (i) limited
or otherwise affected by applicable bankruptcy, insolvency, reorganization,
moratorium, fraudulent transfer and other similar laws of general application
relating to or affecting creditors' rights and (ii) limited by general
principles of equity (regardless of whether considered in a proceeding at law or
in equity), including, without limitation, the availability or unavailability of
equitable remedies and an implied covenant of good faith and fair dealing, and
will be entitled to the benefits of the Indenture.

        We express no opinion as to the laws of any jurisdiction other than the
laws of the State of New York as in effect of the date hereof. Notwithstanding
anything to the contrary contained herein, we express no opinion as to rights
to indemnity and contribution.

        We hereby consent to the filing of this opinion as Exhibit 5.2 to the
Registration Statement and to the reference to our firm therein under the
caption "Legal Matters." In giving this consent, we do not admit that we come
within the category of persons whose consent is required under Section 7 of the
Act or the rules and regulations of the Commission promulgated thereunder.

                                         Very truly yours,

                                         /s/ Winthrop, Stimson, Putnam & Roberts
