The 2002 hit movie, Minority Report is the ultimate precursor for theuse of touch panel displays today. As you may remember, Tom Cruise’scharacter is being blamed for a pre-crime that he has not yet committedand manages to stay one step ahead of the police using a multitude oftouch panel displays as a control center dashboard with information atthe touch of a finger.
Today’s reality is not so far removed fromthis promise of touchscreen technology. Smart phones and tablet PCs arethe most prolific applications for touch panel today. A touch interface allows one to interact directly with a display without the use of akeyboard or mouse and is an enabling technology for the mobile displaymarket which will have sales of around 60 million tablets and 500million smartphones out of a total of close to 1.7 billion mobile phones in 2011 according to published reports. Almost all tablets andsmartphones have touch displays, and touch panel penetration inconventional mobile phones will surpass 50% by 2014.
How do the display manufacturers take advantage of this marketing opportunity and what challenges do they face?
The widespread adoption of touch capability is relatively new in theoverall scheme of display manufacturing. Over the last two years, newcompanies have sprung up mainly in Taiwan and China. Some have createdfactories from scratch; others have converted color filter plants tomanufacture touch panel displays.
There are over a dozen touchscreen technologies including resistive, surface capacitive, projectedcapacitive, on-cell, infrared, optical touch, acoustic wave, digitizer,and others. However, for multi-touch in small/medium displays,projected capacitive has emerged as the clear leader due to itsmulti-touch capability, form factor and reliability. In general terms,capacitive touch works by having two layers of transparent conductor,patterned into an X – Y cross pattern. The two layers are separated byan insulator of glass, or deposited thin film. When a finger touchesthe screen, the electric field is distorted. The location of thedistortion is sent to the controller for processing.
A capacitive touch panel film stack may have over 15 film layers in total and most require at least four or five physical vapor deposition (PVD) layers. Some of the layers are unique to touch panels such asoleophobic coatings that reduce the effects of fingerprint oils andothers that minimize screen wear due to the constant finger or styluscontact.
Applied Materials can help its customers lower costs by increasing the throughput at which our equipment processes panels. However, because the majority of the cost of making a panel is in the panel materials, developing equipment that increasesthe efficiency of raw material consumption is equally important.
The recently announced Applied AKT-Aristo Twin is the first PVD system to utilize two independent vacuum tracksto simultaneously produce two different multi-layer coatings ofmaterials including insulators such as silicon dioxide, transparent conductive electrodes, metals and metal alloys. Rotary target technology provides up to three times the raw material utilization compared to conventional planar targets.
The size of touch panels is expected to grow over the next few years as the technology is adapted for largerapplications such as table top, television or wall displays. Thistransition is easy for the AKT-Aristo Twin, which can handle all glasssizes up to the so-called “Generation 8.5”, which is an enormous pieceof glass or rigid plastic with an area of nearly 60 square feet.
Flexible, efficient and fast touch display manufacturing systems are just whatour customers need to rush us to a touch-enabled future.