Samsung Electronics has begun mass producing its fifth-generation V-NAND memory chips. In the first use of the 'Toggle DDR 4.0' interface, the speed for transmitting data between storage and memory over Samsung's new 256-gigabit (Gb) V-NAND has reached 1.4-gigabits per second (Gbps), a 40-percent increase from its 64-layer predecessor.
Samsung says that the energy efficiency of Samsung's new V-NAND remains comparable to that of the 64-layer chip, primarily because the operating voltage has been reduced from 1.8 volts to 1.2 volts. The new V-NAND also has the fastest data write speed to date at 500-microseconds (μs), which represents about a 30-percent improvement over the write speed of the previous generation, while the response time to read-signals has been significantly reduced to 50μs.
Packed inside Samsung's fifth-generation V-NAND are more than 90 layers of '3D charge trap flash (CTF) cells,' the largest amount in the industry, stacked in a pyramid structure with microscopic channel holes vertically drilled throughout. These channel holes, which are only a few hundred-nanometers (nm)-wide, contain more than 85 billion CTF cells that can store three bits of data each. Samsung claims that this memory fabrication is the result of "several breakthroughs" that include advanced circuit designs and new process technologies.
Thanks to enhancements in the V-NAND's atomic layer deposition process, manufacturing productivity has also increased by more than 30 percent. The technique allows the height of each cell layer to be reduced by 20 percent, prevents crosstalk between cells and increases the efficiency of the chip's data processing.
The first 96L part in mass production is a 256Gb TLC die, which should see broad usage in the mobile and SSD markets. Larger dies will follow to fulfill the need for higher capacities with lower cost per bit, primarily in the enterprise SSD market.
Samsung is also preparing to introduce 1-terabit (Tb) and quad-level cell (QLC) offerings to its V-NAND lineup, confirmed Kye Hyun Kyung, executive vice president of Flash Product and Technology at Samsung Electronics.