State-backed Chinese private equity firm Tsinghua Unigroup Ltd offered to buy US memory chipmaker Micron Technology Inc for $23 billion, The Wall Street Journal reported, citing people familiar with the matter.

Tsinghua offered $21 per share for Micron, which is at a 19.3 percent premium to the stock's close on Monday, the Journal said, citing a person familiar with the matter.

If it goes ahead, the deal would be the biggest Chinese takeover of a US company.

Micron and Tsinghua Unigroup were not immediately available to comment on the report.

Micron makes both dynamic random access memory chips, used mostly in personal computers, and NAND memory chips for storing music, pictures and other data on smartphones, cameras and other mobile devices.

Acquiring Micron's cutting-edge memory manufacturing technology would be a major advance for China's modest but improving chip industry. The country has no major memory makers.

Billionaire hedge fund manager David Einhorn said in an investor letter on Monday that Micron Technology would be worth more than Netflix Inc within the next few years. Netflix was worth $42.9 billion at the close on Monday.