Manufacturing the Touch-Enabled Future
The 2002 hit movie, Minority Report is the ultimate precursor for the use of touch panel displays today. As you may remember, Tom Cruise’s character is being blamed for a pre-crime that he has not yet committed and manages to stay one step ahead of the police using a multitude of touch panel displays as a control center dashboard with information at the touch of a finger.
Today’s reality is not so far removed from this promise of touchscreen technology. Smart phones and tablet PCs are the most prolific applications for touch panel today. A touch interface allows one to interact directly with a display without the use of a keyboard or mouse and is an enabling technology for the mobile display market which will have sales of around 60 million tablets and 500 million smartphones out of a total of close to 1.7 billion mobile phones in 2011 according to published reports. Almost all tablets and smartphones have touch displays, and touch panel penetration in conventional 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 the overall scheme of display manufacturing. Over the last two years, new companies have sprung up mainly in Taiwan and China. Some have created factories from scratch; others have converted color filter plants to manufacture touch panel displays.
There are over a dozen touch screen technologies including resistive, surface capacitive, projected capacitive, 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 its multi-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 by an insulator of glass, or deposited thin film. When a finger touches the screen, the electric field is distorted. The location of the distortion 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 as oleophobic coatings that reduce the effects of fingerprint oils and others that minimize screen wear due to the constant finger or stylus contact.
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 increases the 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 tracks to simultaneously produce two different multi-layer coatings of materials 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 larger applications such as table top, television or wall displays. This transition is easy for the AKT-Aristo Twin, which can handle all glass sizes up to the so-called “Generation 8.5”, which is an enormous piece of glass or rigid plastic with an area of nearly 60 square feet.
Flexible, efficient and fast touch display manufacturing systems are just what our customers need to rush us to a touch-enabled future.