Chip stocks had one of their best days in a decade

  • Xilinix, Teradyne, Lam Research and Texas Instruments all beat earnings expectations in their reports Wednesday, sending the sector surging the next day.
  • Of the 30 stocks on the PHLX Semiconductor Index, only Qualcomm was in the negative.
  • Xilinx's CEO said on the earnings call Wednesday that the global push for 5G helped fuel its growth.
Robert Neely prepares to load a silicon wafer machine in a clean room at the Texas Instruments semiconductor fabrication plant in Dallas, Texas, U.S., on Tuesday, June 16, 2009. Texas Instruments Inc., the second-largest U.S. semiconductor maker, reported sales and profit that beat analysts' estimates on stronger demand for chips used in mobile phones and communications networks in China.  (Photo by Jason Janik/Bloomberg via Getty Images)
Jason Janik | Bloomberg | Getty Images
Robert Neely prepares to load a silicon wafer machine in a clean room at the Texas Instruments semiconductor fabrication plant in Dallas, Texas, U.S., on Tuesday, June 16, 2009. Texas Instruments Inc., the second-largest U.S. semiconductor maker, reported sales and profit that beat analysts' estimates on stronger demand for chips used in mobile phones and communications networks in China. (Photo by Jason Janik/Bloomberg via Getty Images)

Chip stocks surged Thursday after four companies beat analyst expectations on earnings. Of the 30 chip stocks on the PHLX Semiconductor Index, only Qualcomm finished the trading day in the negative.

Xilinx, Teradyne and Lam Research all reported earnings and revenue that beat investors' expectations in their reports Wednesday. The three stocks led the index on Thursday, with Xilinx, which makes programmable chips for data centers, up 18.4 percent, and Lam Research and Teradyne, which make equipment that manufactures semiconductors, up 15.7 percent and 12.9 percent, respectively. Calculator manufacturer Texas Instruments also beat on earnings Wednesday and rose 6.9 percent the next day, despite missing on revenue.

The index overall was up 5.7 percent Thursday compared to the 0.7 percent pop in the tech-heavy Nasdaq Composite Index. It was the seventh-best day for the index in the past ten years.

Xilinx, which creates chip technology for a variety of industries including communications and aerospace, said it has benefited from the global push toward next-generation mobile networks. On the earnings call Wednesday, Xilinx CEO Victor Peng said that within wireless, "the strong growth was primarily driven by 5G deployments in South Korea and a very early start of the ramp of 5G deployments in China."

For Lam, "strong earnings were driven by better-than-expected margins," wrote Romit Shah, an analyst at Instinet, in a note after the report. Shah has a "buy" rating on the stock and said the company's gross margin of 46.3 percent topped Instinet's 46 percent estimate.

The sector could be poised to take a dive on Friday after Intel, the biggest U.S. chipmaker, reported revenue that missed analysts' estimates. Intel shares plunged as much as 8 percent in extended trading on Thursday.

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