Bad news for Applied Materials could be bad news for Lam Research stock as well.Lam Research (LRCX -6.88%), one of a handful of large companies manufacturing equipment for the production of semiconductors, tumbled 6.9% through 1:45 p.m. ET this afternoon. As unbelievable as it may sound, you can blame one of Lam's big rivals, Applied Materials (AMAT -13.82%), for Lam's troubles. Applied Materials' big warning for semiconductor investorsApplied Materials reported strong earnings for its third quarter fiscal ...