News Article
Ushio’s two new “UX4-LEDs” tools prepare for lift off
The new models achieving better cost of ownership by further enhancing productivity and yield for high-volume manufacturing of III-nitride HB LED chips.
Japanese firm Ushio has started shipping what it says is the world's first 200-mm wafer full-field projection lithography tool "UX4-LEDs FFPL 200" for manufacturing High-Brightness LED chips.
The firm has also completed development of the laser lift-off system "UX4-LEDs LLO 150" for volume manufacturing of vertical-structure LED chips.
The latest models of the UX4-LEDs are based on the same platform as Ushio's field-proven UX series, which has an installed base of more than 1,100 systems.
Common UX4-LEDs Platform
The UX4-LEDs 150-mm wafer full-field projection lithography tool, released last November, has already been used for high-volume manufacturing of LED chips at leading LED manufacturers in Japan, Korea, Taiwan, and China, where it has proved its high performance and high reliability.
The UX4-LEDs FFPL 200 is mounted with a full-field projection lens of 200 mm in diameter on the common UX4-LEDs platform to enable full-field projection exposure of a 200-mm wafer. It can achieve a high throughput of 120 wafers per hour. Unlike the stepper systems that lower their productivity as the wafer becomes larger, the UX4-LEDs FFPL 200 uses the full-field projection method to enhance its productivity by increasing the wafer size. Therefore, it allows further enhancement of the productivity and reduction of the cost of ownership in the LED lithography process.
Designed to automatically handle wafer size conversions for up to 200-mm wafers, the UX4-LEDs FFPL 200 is completely non-contact so as to cause no mask damage. The special alignment technology ensures low visibility alignment marks and the large depth of focus and special wafer chucking allows it to cope with warped wafers. What’s more, the modular platform can be upgraded for different wafer sizes. There is also an optional backside alignment function to support LED wafer-level-packaging applications.
The laser lift-off (LLO) technology, for stripping a GaN film from a sapphire substrate, is indispensable to increase LED brightness. Leveraging the photolithography excimer laser known for high repetitive frequency and high stability as well as proven DUV optical technologies, Ushio has developed the UX4-LEDs LLO 150 laser lift-off system. The tool, which is designed to process 150-mm sapphire substrates, can achieve both high yield and high throughput. This system also contributes to significant reduction in LED manufacturing costs because it allows reuse of a sapphire substrate by stripping the GaN film from the entire sapphire substrate surface.
Ushio will exhibit both products through a panel display at SEMICON WEST, booth #2633, South Hall, Moscone Centre, San Francisco, US through 12-14 July 2011.
