Recently, my colleague Kevin Kilbuck told us about new advances Micron has been working on in 3D NAND. This is the latest-and-greatest in NAND Flash technology, and is going to allow advances in data storage everywhere that bits are stored. However, for today, I’d like to focus on how this new technology will affect your home and office computing experience: your PC, laptop, professional tablet and even smart phone.
As Kevin pointed out, until now, NAND Flash devices have had all the memory and logic circuitry laid out in a planar fashion, like a drawing on a piece of paper. In order to store more bits, all these elements needed to be squeezed in a smaller and smaller area within the plane. At 16 nanometers, Micron has had the most efficient planar MLC (multi-level cell) NAND devices on the planet. However, squeezing the dimensions in the planar layout smaller than 16 nm has proven to be a nearly insurmountable challenge. So much of a challenge that industry analysts had started to question whether solid state data storage was going to be able to keep up with the pace set by Moore’s Law.
Gordon Moore, of course, was one of the great pioneers of the semi-conductor industry. He noted (and predicted) that the number of transistors in an integrated circuit (IC) was doubling every two years or so, and would continue to do so. Even though Dr. Moore may very well have offered Moore’s Law with a bit of a wink, it has held roughly true over the decades, and not just for semi-conductors. Hard disk drives (HDD) have exhibited storage capacity and cost reductions which roughly followed Moore, as well.
Mass Storage is Massive again!
When Micron and other companies introduced mass market solid state drives (SSD) over the past decade or so, there was a real challenge to keep up the pace dictated by Dr. Moore. This pace was kept up in a couple of ways for planar NAND. First, the physical dimension of the semi-conductor die continued shrinking, past 25 nm to 20 nm, finally to 16 nm. Second, signal detection capability developed which allowed bit density improvements by storing more than one logical bit in each physical NAND cell. Now, we can store 2 bits per cell (MLC) and 3 bits per cell (TLC). Put simply, as we store more bits in smaller areas, so costs go down, and capacities of SSDs go up.
Of course, the stock in trade of SSD is speed. SSD brought unprecedented speed to desktop computing, in a drop-in replacement for your old HDD. But the complaint remained that if you wanted large storage capacities, SSD wasn’t really a solution. High capacities for desktop computing, say, 2TB and above, were either not available, or prohibitively expensive.
This is where 3D NAND steals the show. After running into this daunting physical challenge of growing storage capacity in two dimensions, given the 16 nm planar barrier, the natural solution is to work in 3D. Building data storage cells in three dimensions solves two problems: now more bits can be stored with better margin in a 3D cell, and the X-Y planar dimensions can be relaxed, allowing better manufacturability.
The net benefit is that 3D NAND allows us to get back on the curve dictated by Moore’s Law. Mass storage is massive again! In the near future, we’ll deliver 2 TB in affordable, convenient and slim 2.5” SSDs, and 1 TB in M.2 SSDs, the size of a stick of gum, for storage in your super-slim Ultrabook and in professional tablets. We will amp up the speed even more in offering these higher capacity SSDs with the PCIe interface, easily doubling the speed at which we can store and deliver data.
High capacity, high speed, compact size: You don’t have to pick one or two!
In point of fact, you may have noticed that laptop HDDs are running into storage limitations, too. Today, the biggest low-profile notebook HDD sits right at 2 TB, just like the biggest notebook SSDs. To reasonably get beyond 2TB, let’s just say it, the HDD has to get huge! Big, heavy 3.5” HDDs with 5 or 7 platters is what it takes to deliver multiple terabytes. This is okay for desktops, but completely incompatible with mobile computing. And, does anyone these days really want a big, clunky mini-tower on their desk? No, desktop computers, where they remain, are shrinking just like notebooks.
Unlike HDD, SSDs are breaking through these limitations. We now have line-of-site to 4 TB small form-factor SSDs and beyond, at prices which won’t break the bank. We also have a performance path which gets future desktop and laptop SSDs to 2,000 MB/s (yes, 2 GB/s!). 3D NAND allows us to deliver this ground-breaking SSD technology, and allows us to further close the price per gigabyte gap with HDD. 3D NAND technology will allow true mass storage in the tiny space allowed by your smart phone, too. No more worries about having enough space to download the latest hit song, or when taking that next photo when your kid scores the winning goal.