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                                                                    EXHIBIT 23.1
 
               CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS
 
     We consent to the reference to our firm under the caption "Experts" in the
Registration Statement (Form S-3) and related Prospectus of Lam Research
Corporation for the registration of $310,000,000 of 5% convertible subordinated
notes due 2002 and up to 3,531,958 shares of Common Stock, and to the
incorporation by reference therein of our report dated August 26, 1997, with
respect to the consolidated financial statements of Lam Research Corporation
incorporated by reference in its Annual Report on Form 10-K for the year ended
June 30, 1997, and our report dated August 26, 1997, with respect to the
supplemental consolidated financial statements and schedule of Lam Research
Corporation included herein.
 
                                          /s/  ERNST & YOUNG LLP
 
San Jose, California
October 28, 1997
