Whether your photomask inventory contains 100 or 10,000 pieces, it represents both a significant financial investment and an important embodiment of your intellectual property. Keeping your mask inventory functional and available is integral to the smooth operation of your lithography area. At Toppan, we understand the critical nature of this task and we’ve established services to assist you in the management of this key resource.
Pellicle membranes are protective films that keep particles out of the focal plane of the mask. They are also highly engineered specialty components designed to maximize transmission without causing aberrations. Unfortunately, pellicles are also very delicate. They are easily scratched, punctured, torn or become contaminated, delaminated, or can even be completely removed from the mask.
Pellicles are often damaged at the worst possible time — when a lot is waiting. Toppan is an expert for this exact situation. We customize our pellicle process flow ahead of time to match your requirements for each layer. And we pre-determine the fastest possible logistics so that you know when to expect your photomask back in the fab, hour by hour and across the whole week, even down to the flight numbers and truck delivery times.
Included with each repelliclization is a full cleaning and recertification of your photomask. Each of these steps is uniquely tailored for your products and needs, providing you fast speeds while ensuring the highest product quality.
RecertificationBack To Top
Almost all of our customers have internal programs that certify that their photomask inventory is in top working condition. Typical recertification triggers used in the industry are:
- Recertification after some cumulative dose or wafer count
- Recertification after some period of time
- Automatically reclean after some period of time or cumulative dose
- Recertification when damage is suspected
Toppan offers fully customized Recertification Services. Every Recertification begins with a thorough visual inspection of both the photomask and pellicle to note any macroscopic damage. We then offer a variety of microscopic inspections tailored for your unique quality and cycle time needs.
We offer multi-surface particle inspections, pattern integrity inspections, STARlight inspections and, for phase-shift masks, phase and transmission measurements. These inspection results and measurement values are compared back to the original outgoing data to determine if there has been any damage or changes at the microscopic level. Our goal is to give you back a fully functioning photomask that's as good as new.
CleaningBack To Top
Backside Glass Cleaning
For single-pellicle products, simple handling and storage can accumulate particles on the backside glass surface. Additionally, environmental haze growth on the glass can reduce transmission through the photomask.
But when the patterned surface is still clean and the backside glass is contaminated, it is unnecessary to perform a full repelliclization. Instead, you need a simple backside clean to return your photomask to working condition. This pragmatic and fast service is designed to minimize the time your mask is out of the fab. All Toppan locations around the world support high-quality backside cleaning with fast turn times to help you keep your fab running.
Patterned Surface Cleaning
We have a suite of patterned surface cleaning technologies engineered for our customers' various applications. The process begins with removing the old pellicle from the photomask followed by state-of-the-art cleaning to ensure both proper adhesive removal and elimination of foreign contamination.
Our patterned surface cleaning technologies are designed to operate in a perfect sweet spot — aggressive enough to clean the surface and gentle enough to not damage the absorber, be it either chrome or MoSi. For phase-shift photomasks, our clean processes minimize both phase loss and transmission degradation. We measure the minor changes to phase and transmission and provide you these results for your record keeping. And for leading edge 193nm masks, our most advanced cleaning processes preserve small, delicate features while achieving low ionic residuals.
Quartz Blank RecyclingBack To Top
Our popular Quartz Blank Recycling program is one of many eco-friendly, environmental projects we've run over the past decade. We purchase used quartz substrates from wafer fabs and transform them into new photoblanks that meet virgin material specifications. We buy both binary and MoSi photomasks, including ITAR materials. Any substrate that cannot be reused is securely destroyed.
Our recycling program saves you valuable space by eliminating unnecessary internal inventory. We conduct proper environmental disposal of chromium, so you can avoid any regulatory hang-ups. The program also helps to keep photoblank costs down through reuse and repurposing. And best of all, we pay you for the material! To date, our program has processed over 1 million quartz substrates!