Lam Research stock was pacing toward its best day in 27 years on Thursday, drawing a stark contrast to an industry peer's post-earnings slide.

Lam shares spiked 23% to $310.69, putting them on track for their largest same-day percentage increase since January 1999, according to Dow Jones Market Data.

The rally came after the maker of semiconductor equipment posted stronger-than-expected fiscal fourth-quarter earnings.

After Wednesday's closing bell, Lam reported adjusted earnings of $1.82 a share, ahead of the $1.69 analysts had anticipated. Sales climbed 30% to $6.72 billion, beating Wall Street's call for $6.66 billion.

For the current quarter, Lam projects adjusted earnings of $2.15 a share on sales of $8.1 billion. Analysts were looking for profit of $1.84 a share and sales of $7.11 billion.

UBS analyst Timothy Arcuri reiterated a Buy rating and $435 price target on the shares following the report. Lam's numbers and guidance "were very strong, particularly the service business as NAND customers are trying to increase bit production with limited wafer volume expansion," he wrote.

Lam's earnings were lifting peer stocks in the broader semi equipment and materials industry. Applied Materials and KLA Corp. advanced 13% and 7.6%, respectively, on Thursday.

Although Lam's latest numbers were helping it snap a four-day losing streak, KLA's fiscal fourth-quarter earnings failed to stem its selloff, as analysts noted the bar was set much higher heading into the report.

Even counting Thursday's gains, KLA stock has fallen 39% in July, putting it on pace for its worst monthly performance since October 1987.

Jefferies analyst Blayne Curtis noted on Wednesday that KLA had eked out "only a modest beat," though momentum was beginning to reaccelerate in the business.