Micron Technology closed above $1 trillion in market value on Tuesday, becoming the 12th U.S. company to cross that threshold and the first based in Idaho. Shares jumped 19% as the Boise memory chip maker solidified its place as the latest flag-bearer of the semiconductor rally, lifting the S&P 500 and Nasdaq.

The stock has climbed roughly 80% in the past month, reaching the $1 trillion mark just 48 days after first hitting $500 billion. Nvidia took 490 days to clear the same benchmark, making Micron's ascent the fastest run to a 13-figure valuation on record. Dan Russo of Potomac called the pace "unprecedented."

For years Micron was treated as a commodity play, making simple memory chips that attracted little investor attention. That has shifted dramatically. Michael Rosen at Angeles Investments now calls it "the poster child" of the AI chip boom, as even the most basic elements of the AI build-out get swept up in the yearlong frenzy for semiconductor stocks.

The speed of Micron's rise underscores how aggressively capital is flowing into the semiconductor sector. With the S&P 500 and Nasdaq both benefiting from the stock's surge, the rally has become harder to ignore for investors still on the sidelines.