Broadband wafer steppers, also known as 1X Steppers or Mini-Steppers play an essential role in today’s advanced packaging applications, such as Fan-Out Wafer-Level Packaging (FOWLP), Wafer-Level Chip-Scale Packaging (WLCSP) or Through Silicon Via (TSV). Complex microstructures like MEMS or LED’s are prominent examples to be manufactured on those highly specialized step-and-repeat lithography systems.
Our broadband UV-LED light sources ALE/1 and ALE/1C are a perfect fit, if you want to upgrade your stepper to UV-LED illumination. By adopting our solution, you gain full flexibility on the choice of photosensitive advanced packaging materials you may need to apply in your process.
It is a unique setup that we use: Combining individual LED-Modules around the i-, h-, and g-line into one optical path allows you to have full control on the spectral composition of your broadband exposure in the 350-450 nm range. As we provide high-power radiation output, you can replace any conventional mercury arc lamp with a rated power of up to 1,000 W or even higher. Forget about tool downtime while swapping lamps and the hassle of mercury waste disposal. With our UV-LED technology integrated in your lithography tool, this is a thing of the past.
Our systems prove themselves daily in countless semiconductor manufacturing applications. Using our high-performance UV-LED illumination technology in a wafer stepper, you can achieve resolutions down to 1 µm or even in the sub-micron range. The excellent output stability and reliability substantially facilitate the industry’s efforts to leverage system throughput (WPH) while bringing the cost of ownership down.
Our UV-LED exposure solutions replace the conventional lamp house and eliminate the need for the primary beam folding mirror, heat sink to absorb radiation over 450 nm, shutter, and filters. In many cases, our LED Performance Optics are also an economical alternative for existing homogenizing / condensing components. You have two options to upgrade your wafer stepper from mercury arc lamps to our UV-LED illumination:
We can customize both solutions to perfectly fit into your equipment. Retrofitting your existing system is also possible.
|Output Power [mW]||Broadband|
Mercury Discharge Lamp (typical values)
1Standard mode; Performance mode with chiller delivers additional 20% output.
Switching time (0 to 100%) of our UV-LED exposure solutions is below 1 millisecond. Furthermore, an internal closed-loop feedback control system guarantees constant radiation output over short as well as longer exposure cycles. These features permit dose accuracies of ±0.2% for short 50-millisecond shots just by using a timer. The accuracy even increases for longer exposure cycles (e.g., 300 milliseconds).