According to the technology roadmap released by INSIC in 2019, magnetic tape has increased the recording density by an average of 34% / year (1994-2018), and as of 2019, the uncompressed capacity per cartridge achieved 20 TB bytes. It is said that the average growth rate will continue to be 34%, and the capacity of one tape in 2029 will reach 723TB.

HDDs, on the other hand, the recording density has only increased by an average of 7.6% / year over the last decade. This is a much lower growth rate than it was previously predicted. HDDs are facing the physical limits of magnetism called superparamagnetism*. The forecast for future growth of HDDs is uncertain because new technologies need to be introduced to increase the recording density.

The recording capacity is determined by the recording density x recording area. The maximum capacity of current HDD products is 16TB (as of 2019) with nine 3.5-inch size disks. Since tape can record a large area on a film that is 0.5 inches wide and 1 km long, the recording capacity exceeds that of an HDD even if the recording density is small. There are four key technologies of tape to achieve its future roadmap.

First is the media technology which requires a fine particle magnetic material to achieve the SNR (Signal to Noise Ratio) and a thin base film to wind the tape kilometers long. Research on new materials such as Strontium Ferrite and ε Iron Oxide has started as candidates for future magnetic particles.

Next is the head technology that requires a highly sensitive micro reader and a high output writer to read and write minute recording bits. In 2017, the tape drive replaced the GMR reader with the sensitive TMR reader used in HDDs. The size of the TMR head of tape is still 400 times larger than that of HDD, so it is possible to miniaturize it in the future. Also, for writers, the introduction of the monopole lighter used in HDDs can effectively generate a stronger recording magnetic field.

Third is the tape transfer system of the tape drive. In the future, the track width on which data is recorded will be as narrow as 121 nm. High-precision mechanical system that can suppress vibration so that the drive head does not come off the track while running with high speed will be required.

The last is the signal processing technology. It is related to the error correction capability that automatically repairs errors (bad bits) when reading the data. By utilizing the strong Reed-Solomon codes C1 and C2, the error rate is as high as 1 x 10-19 with LTO8. In the future, the goal is to further reduce this error rate to 1/10.

Although the roadmap states that the capacity of one tape cartridge in 2029 is 723TB, the recording density (278Gbpsi) at this time is about the same as that of HDD products in 2008. There is still room for tape evolution and with continuous technological development aimed at the roadmap; 1PB cartridge may become a reality in the future.