Solid state drives (SSDs) have become increasingly popular in recent years as an alternative to traditional hard disk drives (HDDs). SSDs offer much faster read and write speeds, better durability, and quieter operation compared to HDDs. As SSD technology continues to advance, SSD storage capacities have been steadily increasing as well. Consumer SSDs with capacities up to 4TB are now readily available from major manufacturers. This begs the question – do SSDs currently exist with even higher capacities, such as 5TB?
Brief Overview of SSD Technology
Before diving into the specifics on maximum SSD capacities, it helps to understand what exactly SSDs are and how they work. SSDs utilize flash memory chips rather than magnetic platters and read/write heads as found in traditional HDDs. The most common types of flash memory used in modern SSDs are NAND-based, which can be further broken down into Single Level Cell (SLC), Multi Level Cell (MLC), Triple Level Cell (TLC), and Quad Level Cell (QLC) configurations. Higher density flash memory types like TLC and QLC allow for greater storage capacities but typically have shorter lifespan and slower performance.
Data is stored on flash memory chips inside an SSD using interconnected flash memory cells. These cells trap electrons on a floating gate layer which defines the stored data state. SSDs use a controller to manage all operations on the flash memory and also often includes a DRAM cache. Reads and writes to an SSD do not involve any mechanical moving parts or physical seeking like with HDDs, allowing for much faster access times.
History of Increasing SSD Capacities
In the early days of SSDs, capacities were very limited, just a few gigabytes. This restricted SSD adoption mostly to enthusiasts and niche use cases. As the technology matured and evolved from SLC to MLC and then to denser TLC and QLC configurations, SSD capacities steadily increased over the years. Some key milestones in the advancement of higher capacity SSDs include:
– 2009 – Intel released the first consumer SSD with over 100GB capacity using 34nm MLC flash.
– 2011 – SSDs reached 256GB capacities, allowing them to rival laptop HDD capacities for the first time.
– 2012 – Samsung introduced the first 1TB SSD using 19nm TLC NAND flash.
– 2015 – 2TB SSDs hit the mainstream consumer market led by Samsung’s 850 EVO and Pro models.
– 2017 – 4TB SSDs arrived as density pushed higher with 64 layer 3D NAND flash chips.
– 2019 – NAND flash manufacturers began sampling and producing 96 layer QLC NAND flash chips, promising even higher capacities.
This consistent growth of SSD capacities over the years has been enabled by steady advances in NAND flash technology allowing for greater density and bits per cell. Even larger SSD capacities seemed inevitable. But have we now reached the upper limits, or might 5TB consumer SSDs soon be possible?
Manufacturing Limits on NAND Flash Density
There are both technological and economic constraints governing just how high SSD capacities can currently go. On the technical side, NAND flash manufacturers continue to try to shrink the lithography process size used in production. However, there are physical limitations to how small the cells can become before electrons leak through the thin insulating oxide layer. Most industry experts believe process sizes below 10 nanometers will prove extremely difficult with conventional planar NAND flash technology. Even as some manufacturers like Western Digital and Micron have started sampling 96 layer QLC NAND, scaling beyond 100 layers using current approaches also seems improbable. There are a few emerging technologies like 3D XPoint from Intel/Micron that may eventually supersede NAND flash, but none are ready yet for prime time.
So for now, 96 layer QLC NAND likely represents the practical upper limits of what can be achieved. With 1 terabit (128GB) per die densities possible, this allows for up to 16TB of raw NAND flash per SSD assuming 16 die per package and 8 packages. However, after accounting for overprovisioning, RAID configurations for redundancy, and controller and interface overhead, this works out to a maximum usable capacity around 8TB. While not fundamentally impossible, producing a consumer SSD higher than 8TB with existing NAND technology would require compromises in performance, endurance, or cost.
Economic Viability of 5TB SSDs
The difficulty and expenses associated with pushing SSD densities higher using current NAND flash also impose economic constraints. As process geometries shrink below 30nm, costs rise exponentially. Facilities must be overhauled for EUV lithography and other advanced fabrication techniques. Yields tend to suffer with each die density jump as defects become more likely. This leads to substantial price inflation on higher density SSDs.
For example, while a 1TB SSD may retail around $100, a 2TB model generally costs around $200-$250 and a 4TB version $400-$500. If these capacity jumps came with a linear price increase, a 5TB SSD would be expected to cost over $600 using QLC NAND. But realistically, a 5TB SSD built with higher density QLC would likely retail closer to $800 given the manufacturing challenges involved. And the performance, write endurance, and usable lifespan would be impacted trying to push right up against the limits of 96 layer QLC technology.
Most consumers are unwilling to pay several hundred dollars extra just to gain 1TB more SSD capacity of questionable longevity. For that kind of money, they could almost buy a second drive. And data center and enterprise buyers are more focused on performance and reliability than maximizing absolute capacity. So there is not much current market demand or incentive for manufacturers to produce and sell 5TB consumer SSDs when more cost-effective methods like larger HDDs or RAID arrays exist to add storage capacity.
Advancements Needed for 5TB SSD Viability
For consumer 5TB SSDs to become economically viable to produce and purchase, some technology advancements will be necessary. Most importantly, the NAND flash process will need to shrink below 96 layers at under 10nm geometries. Research is already underway on possible replacements for floating gate flash memory, including options like:
– 3D V-NAND – Adds vertical channels to TLC and QLC for increased density.
– MRAM – Stores data magnetically using magnetic tunnel junctions. Enables much faster writes.
– RRAM – Resistive RAM cells change resistance to represent data states.
– PCM – Phase change memory utilizes crystalline structures in chalcogenide glass.
– FeRAM – Ferroelectric RAM uses ferroelectric film polarization to indicate data.
It’s likely a transition to one of these developing non-volatile memory technologies will be required before 5TB 2.5″ SSD form factors become feasible. Costs also need to decrease substantially as emerging memory progresses from niche applications to mass production scale.
Other SSD components like controllers and interfaces will need to improve as well. For example, current NVMe PCIe 4.0 x4 interfaces used in many SSDs provide up to 4-5GB/s bandwidth. This may prove limiting for high capacity drives. PCIe 5.0 and new form factors like EDSFF aim to remove those IO bottlenecks. Power efficiency will also become more crucial with multi-TB drives to avoid thermal throttling issues.
Realistically, it will probably be at least 2-3 more years before all these ingredients align to make a 5TB SSD viable in the consumer space, assuming no major breakthroughs. But there are strong incentives so capacity limits keep being pushed upward.
Which SSD Brands Might Release 5TB First?
Based on their past leadership bringing higher capacity SSDs to market, a few manufacturers seem most likely to be the first to introduce a 5TB SSD once that milestone becomes possible.
**Samsung** – They have consistently been on the leading edge of NAND flash production and SSD development. Examples include releasing the first 4TB QLC SSD and demonstrating a whopping 30TB drive using exoticStacked V-NAND design. Their dominance of the SSD market share gives Samsung the resources and demand to pursue next-gen advancements.
**Western Digital** – Their SanDisk subsidiary has partnered with Toshiba to co-own critical NAND flash fabs. And they now own other important flash IP after acquiring STEC, Virident, and Fusion-io. As both a NAND manufacturer and SSD brand, Western Digital has all the in-house pieces needed to make 5TB drives a reality.
**Seagate** – Though more known for HDDs, they have invested heavily in SSDs in recent years through acquisitions like LSI/SandForce, Samsung’s HDD business, and LaCie. Partnering with Intel/Micron on new 3D XPoint memory could give Seagate early access to enabling technologies for 5TB SSDs as well.
**SK Hynix** – This Korean semiconductor firm is one of the top three NAND flash manufacturers. So they have the ability to supply the high density flash memory likely needed to hit 5TB capacities. Expanding their downstream SSD business with innovative products is a natural next step.
**Intel** – The original inventor of 3D XPoint memory and Optane SSDs has a reputation for pioneering storage tech breakthroughs. And Intel’s ownership of IMFT fabs provides access to leading edge manufacturing capabilities. Once 3D XPoint or other new memory hits cost parity with NAND, Intel may quickly offer super high capacity SSDs.
Of course unexpected challengers could also emerge to beat the established players to 5TB drives. But Samsung, WD/SanDisk, and Intel seem best positioned currently. Though ultimately advancing NAND flash and alternative non-volatile memory tech is vital so the entire SSD industry can offer even higher capacities.
Use Cases for 5TB SSDs When Available
Although still a ways off, 5TB SSDs would provide some unique benefits for certain use cases whenever they do arrive. Some examples include:
**Gaming Rigs** – Enthusiast PC gamers always demand bleeding edge hardware. A 5TB internal M.2 NVMe SSD would provide vast storage for huge game libraries without sacrificing load speeds.
**Media Editing** – The RAW high-res photo and video files used in media creation chew through local storage space. A 5TB SSD RAID would offer responsive scratch space for editing projects.
**Scientific Data** – Research simulations and genomic datasets often exceed storage limits. A compact 5TB SSD is easier than racks of HDDs or tape.
**Servers** – Online services require speed and capacity. A 5TB SSD can replace arrays of smaller disks to reduce footprint and TCO.
**Cloud Storage** – Hyperscale data centers need efficient scalable storage. High density SSDs like a 5TB drive maximize racks and reduce costs.
**NAS & Backup** – Home media servers and backup targets require ample capacity. A 5TB SSD provides file redundancy without relying solely on external drives.
Conclusion
In summary, while SSD capacities have grown steadily over the years, 5TB 2.5″ SSD options are not yet available for consumer purchase. Fundamental technical limitations of current 96 layer QLC NAND flash memory restrict capacities below 8TB. And the substantial expense and questionable reliability of pushing flash that far makes 5TB SSDs cost prohibitive for now.
Significant innovations in non-volatile memory technology along with improved SSD architecture will be needed before reaching the 5TB SSD milestone becomes economically viable. Leading candidates like Samsung, WD/SanDisk, and Intel are best positioned to get there first based on their access to next-gen memory IP and manufacturing scale. But it still may take 2-3 years or more before the necessary advancements materialize to enable 5TB SSDs.
When that day eventually comes, early adopter consumers and various professional use cases will find great benefit in 5TB of solid state storage capacity. But for those who currently need more than the maximum 4TB SSD options available, adding secondary hard drives in RAID or NAS enclosures remains the most practical solution.