Disk drive manufacturers need higher levels of cleaning
Chang-Gyu Hwang, president of Samsung Semiconductor, once predicted that the capacity of flash memory chips will double every year. This law has been established for five years. The capacity of the 32 Gigabit chips that came out at the end of 2006 was twice that of 2005 and 64 times that of 2000. According to Hwang's law, disk drive manufacturers need to better address pollution control issues.
Intense competition within the industry forces hard drive manufacturers to implement more stringent pollution controls. Images are available from Hitachi GlobalStorage Technologies.
Joseph Unsworth, principal analyst at Gartner Dataquest Semiconductor, said the trend will continue until 2010, when the price of flash memory falls by more than 50% per year. Unsworth pointed out that this development prospects pose challenges to disk drive manufacturers. He said: "As prices continue to drop and capacity continues to increase, then you should target new applications, such as hard drives."
Hard disk drive manufacturers are implementing more stringent pollution control, partly because of this factor, but the main pressure is from internal competition in the industry. According to ClintDyer, executive vice president of Hitachi Global Storage Technologies in San Jose, Calif., the main measure is density, the amount of data stored in disk space, and how to increase its value is the most important. He said: "We must increase the density of the product, which requires a higher level of cleanliness."
For the hard disk, the most important is the distance between the head and the rotating chassis, and the gap between the magnetic fields on the chassis. They are only a few nanometers. Pollution control solutions include the use of Class 10 (ISO Class 4) clean rooms in the most important areas, the use of carefully selected materials, automated assembly lines and other measures.
Hardy maker Seagate Technology spokesperson ForrestMonroy said that Seagate has a Class 100 (ISO Class 5) clean room in Singapore that can be upgraded to an ISO Class 4 clean room. Seagate has nine cleanrooms in the facility, each covering an area of 150 x 100 square feet. Efforts to reduce pollution include strict control of electrostatic discharge, comprehensive training and automation of personnel.
John Monroe, vice president of research and development at Gartner, said these pollution control technologies increase density and product yield. However, this comes at a price because the hard drive is a mechanical device with outgassing and vibration, and this mechanism is expected to last for many years. Monroe said: "Pollution can cause magnetic field failure, which can be catastrophic."
Strict control of electrostatic discharge, comprehensive training of personnel and the use of automation technology can increase density and product yield. Seagate Technology provides photos.
Despite these efforts, disk drive manufacturers face a challenge in how to make flash memory robust in some products. The manufacturing price of the hard drive is fixed and is now around $40. For low-volume requirements, the price of flash memory may be lower than the cheapest hard drive. However, better pollution control can increase production and lower the price of hard drives.
On the other hand, hard drive manufacturers are taking advantage of Hwang's law. Some manufacturers have announced hybrid drives, a drive that uses both a rotating chassis and flash memory. This type of drive is dormant most of the time, which saves power and spins less than a minute per hour during normal use. Hybrid hard drives are expected to move quickly in the next few years.