CXMT mass-producing G5 DRAM as new 24Gb chips reach flagship phones

Chinese memory-chip maker CXMT said on Sunday that it has begun mass production of a new-generation DRAM manufacturing platform approaching the industry's most advanced production processes, marking another step in China's drive to close the technology gap with global semiconductor heavyweights.

Its latest 24-gigabit LPDDR5X memory chip has also entered mass production and is already being used in mainstream Chinese flagship smartphones, CXMT said.

At the World Manufacturing Convention held in Hefei, CXMT vice-president Luo Xiaodong said that the chips are built on CXMT's newly mass-produced fifth-generation, or G5, DRAM technology platform and hold 50 percent more data than equivalent products from its previous generation.

Luo said the new products had "fully entered" mainstream domestic flagship smartphones, although he did not name handset makers or individual models. "Our process capability is now on par with the most advanced mass-produced nodes in the industry," Luo said.

The chipmaker said its G5 platform uses quadruple patterning to shrink the active-area half-pitch in its DRAM memory array to 11.95 nanometers, close to the level of the industry's most advanced mass-produced DRAM processes. The figure refers to a physical feature measurement in the memory array rather than a conventional logic-chip process-node name.

The company also said it had achieved a 45:1 capacitor aspect ratio and reduced the height of a key functional area to 6,762 nanometers using a high-k metal gate, or HKMG, process adapted for DRAM manufacturing. Those changes allow CXMT to pack more memory into the same area of silicon.

The G5 platform can produce at least 50 percent more gross dies per wafer than CXMT's fourth-generation platform, the company said. The comparison is calculated on an 8Gb-equivalent basis and refers to the number of potential dies cut from a wafer before defective chips are screened out, rather than a 50 percent increase in manufacturing yield.

CXMT unveiled two G5-based LPDDR5X products on Sunday. Each has a 24Gb die density, 50 percent higher than the comparable previous-generation product, and comes in either a 496-ball or 245-ball package for smartphones and other portable electronics. Both are in volume production.