The new Mozaic 3+ platform uses a bunch of new technologies, including new media, new heads, and a new controller. It will be used for Seagate's upcoming Exos hard drives for cloud datacentres with a 30TB capacity and higher. Heat-assisted magnetic recording is supposed to boost the amount of data that can be stored on magnetic media by heating it up before writing.

Seagate's Mozaic 3+ uses 10 glass disks with a magnetic layer made of iron-platinum that lasts longer and has smaller grains than normal HDD platters.

To write the media, the thingy uses a plasmonic writer thingy with a tiny laser that heats the media before writing. Because the grains are so small with the new media, their magnetic signals are lower, and the magnetic noise is higher.

As a result, Seagate had to make its new Gen 7 Spintronic Reader, which has the "world's smallest and most sensitive magnetic field reading sensors", according to the company.

Because Seagate's new Mozaic 3+ platform deals with new media with small grains, a new writer, and a reader that has many small magnetic field readers, it also needs a lot of computing power to make the drive work. So Seagate has given the Mozaic 3+ platform a new controller made on a 12nm process.