The cycle of each processing step for 193NM CALCIUM FLUORIDE WINDOW SHEET

Processing Flow and Cycle of 193NM CALCIUM FLUORIDE WINDOW SHEET (Technical Specification) 

193NM CALCIUM FLUORIDE WINDOW SHEET (193nm fluorite window sheet) is core adapted to the 193nm ultraviolet band. Relying on the excellent ultraviolet transmittance and low dispersion characteristics of calcium fluoride (CaF₂) substrate, it is widely used in high-precision optical scenarios such as deep ultraviolet lithography, ultraviolet spectroscopy analysis, and excimer lasers. The processing flow requires strict control of substrate purity, surface shape accuracy and surface quality. Each process has standardized cycle control to ensure both production efficiency and product accuracy. The following is a detailed processing flow and corresponding cycle description (calculated based on a batch of 100 pieces, regular specifications Φ25-50mm, thickness 1-3mm. Customized specifications cycle can be adjusted as needed). 

I. Core Processing Flow and Corresponding Cycle (Full-process Closed Loop, Cycle Controllable) 

1.Processing procedures 

Core operation content 

Standard cycle (batch of 100 pieces) 

Cycle Description (Influencing Factors) 

Base material selection and inspection 

Screen high-purity calcium fluoride (CaF₂) substrates, test their optical homogeneity, purity, stress and 193nm band transmittance, and discard the unqualified substrates. 

1 to 2 days 

The purity test of the base material needs to be precisely controlled. For larger batches, the testing period can be appropriately extended by 0.5 to 1 day. 

2. Substrate pretreatment (cutting + cleaning) 

The diamond wire saw cuts the raw material blanks to the preset size at low temperature. After three-stage purification cleaning (ultrasonic + plasma + nitrogen blow dry), they are sent to the clean room for standby. 

2 to 3 days

The cutting accuracy needs to match the requirements of the 193nm band, and the cleaning needs to reach a 100-level cleanliness standard. The thicker the thickness, the cutting cycle increases by 0.5 days. 

3. Preparation of Specialized Fixtures and Loading onto the Disk 

Customize a stress-free fixture adapted to calcium fluoride substrates, using a hot-melt adhesive to fix the substrate and protect the edges, ensuring the stability of the processing. 

One day 

The fixture can be reused. An additional one day is required for the first preparation. For batches of 50 pieces or less, it can be shortened to 0.5 days. 

4. Outer Forming and Chamfering 

Milling and grinding to form (round/square), precisely controlling the external dimensions, using diamond chamfering wheels for 45° chamfering to remove sharp edges and prevent chipping. 

Two days

Special-shaped specifications require an additional one day. The higher the chamfering accuracy requirement (≤0.2mm), the cycle increases by 0.5 days. 

5. Fine grinding (flat surface + precision calibration) 

Planar precision grinding, controlling the parallelism and thickness tolerance of the substrate, and initially calibrating the surface flatness, lays the foundation for polishing. 

3 to 4 days 

The surface roughness Ra should be controlled to be no more than 1.6 μm, and the parallelism should be no more than 0.1 arcmin. The higher the precision requirement, the longer the cycle. 

6. Ultra-precision polishing 

Under a 100-level clean and constant-temperature environment, using dedicated polishing liquid and polishing cloth, ultra-precision polishing is achieved to ensure the surface shape accuracy and surface quality. 

4 to 5 days 

The core process, which needs to achieve a surface shape accuracy of λ/10 @ 632.8nm and Ra ≤ 0.2nm, is one of the processes with the longest cycle. 

7. 193nm dedicated film coating (optional) 

In an ultra-high vacuum environment, a 193nm band antireflection coating is deposited to enhance the transmittance, and an annealing treatment is carried out to strengthen the adhesion of the film layer. 

3 to 4 days 

If no coating is required, this process can be omitted. For high-end customized coating systems (such as high-transmission anti-reflection coatings), an additional 1-2 days will be needed. 

8. Bottom Plate and Precision Cleaning 

Heat the de-gumming lower plate to remove the residual gum layer on the surface, precisely clean the surface impurities, and after drying with nitrogen, send it to the inspection area. 

One day 

When cleaning, avoid scratching the surface. For large batches, it can be processed in several batches without extending the cycle. 

9. Comprehensive Finished Product Inspection 

Test the angle accuracy, surface shape accuracy, dimensional tolerance, 193nm band transmittance, and coating performance (if any), and issue a test report. 

2 to 3 days

All finished products will be inspected. Unqualified products need to be reworked, which will add an extra 1-2 days to the cycle. 

10. Packaging and Outbound Shipment 

Special anti-static and anti-scratch packaging, individually sealed, with a test report attached. Products will be dispatched after the information is verified. 

Half a day 

The larger the batch, the packaging cycle can be appropriately extended by 0.5 days. Customized packaging does not add extra time to the cycle. 

II. Periodic Summary and Explanation 

1.Standard total cycle: 

For regular specifications (no coating required), the total processing cycle for a batch of 100 pieces is 16.5 to 21.5 days; if coating is required, the total cycle is 19.5 to 25.5 days.

2. Customized specification impact: 

Irregular dimensions, special thickness (＞3mm), and high-end film system customization can extend the total cycle by 3-5 days; small batch (≤50 pieces) can shorten it by 2-3 days. 

3. Cycle Assurance: 

UltraOpto adopts a standardized production process, with dedicated personnel controlling each procedure to optimize production flow and ensure controllable cycles. In response to urgent customer demands, production priorities can be coordinated and adjusted to shorten the delivery cycle (by up to 3-4 days at the fastest). 

4. Core Explanation: 

The processing cycle of 193nm calcium fluoride window plates is mainly influenced by the polishing and coating processes. These two processes require precise control of process parameters to meet the strict requirements of the 193nm deep ultraviolet band. The processing cycle should not be blindly shortened to avoid affecting product accuracy. 

III. UltraOpto's Cyclical Advantage 

1.Standardized control: 

The cycle of each process is clear, production links smoothly, and there is no redundant time consumption, ensuring delivery timeliness. 

2. Balancing precision and efficiency: 

Optimize the processing technology to maximize the shortening of the core process cycle while ensuring the fitting accuracy in the 193nm band. 

3. Customized adaptation: 

According to the batch and specification requirements of customers, the production cycle can be flexibly adjusted, and expedited delivery services can be provided. 

4. Transparent and traceable: 

During the production process, the progress of each procedure can be fed back to customers in real time, ensuring that customers are informed of the production timeline and can wait for delivery with peace of mind. 

UltraOpto, relying on its mature 193nm calcium fluoride window processing technology and standardized cycle control system, ensures high precision and stability of the products while achieving efficient production. It provides timely and reliable product delivery support for high-end applications such as deep ultraviolet lithography and excimer lasers.