Attachment 1 -Specifications Updated 30 May 2025.pdf

Specifications for Photoresist Direct Write Lithography System

Section 1. General Requirements

1.1 Scope. ‐ This specification describes the minimum technical requirements and the minimum acceptable performance standards for a photoresist direct write lithography (PDWL) system.

The PDWL tool will be placed in a multiple user facility and must provide ease of operation and safety to those in the facility.

1.2 Installation Site. ‐ The vendor shall install the tool at the Naval Research Laboratory, Washington

DC 20375, Building 250 in a Class 100 clean room at a location to be designated by the

Contracting Officer's Representative (COR). The vendor shall install the tool in a manner consistent with typical clean‐room operating procedures. The tool is to be compatible with provided utilities: 120 VAC single phase and 208 VAC single and 3‐phase electrical power, compressed air, process chilled water, and liquid and dry gas nitrogen supply, and in a temperature and humidity‐controlled cleanroom workspace.

1.3 Description and Primary Tool Components. ‐ The system is nominally composed of a vibration‐ isolated structural frame, a mounting table supporting the substrate, optical components that implement direct writing (optical exposure) over the surface with selectable resolution and programmable dose values, and a computer control system that will utilize CAD input files that, via a computer‐based user interface, will execute the direct write exposure of a photosensitive film atop a flat substrate. Detailed requirements follow.

Section 2. Mechanical requirements

For discussion, the direction perpendicular to the writing surface is considered the z‐axis. The x‐ y plane is normal to the z‐axis and considered the surface of the substrate. The dimension “nm” refers to nanometer; “mm” refers to millimeter.

2.1 Substrate size: The substrate mount must be capable of holding substrates from 5 x 5 mm square to 250 mm DIA and providing controlled exposure of areas from 5 x 5 mm to 200 x 200

mm. The system must support patterning of flat substrates up to 10 mm thick. Automated focus capability is required to maintain resolution over full exposure area of the wafer.

2.2 Option. The vendor must provide capability to support fragile and samples as small as 3 x 3 mm.

2.3 The combined mechanical and optical components and computer control must automatically identify the substrate boundaries in x and y directions. The system must, at minimum, automatically determine substrate boundaries for circular and rectangular substrates.

2.4 X‐y position repeatability must be 50 nm or less with positional resolution of 10 nm or less.

2.5 In addition to x‐y position control, the vendor is to provide motorized z‐adjustment to accommodate various thickness flat substrates up to 10 mm thick for direct write patterning and automatic focus adjustment.

2.6 Option. A HEPA‐filter fanbox and enclosure is to be provided to minimize contamination by particulates during operation.

2.7 The system must occupy a space less than 1000 x 1500 x 2000 mm (Width x Depth x Height).

2.8 The system must be equipped with isolation mounts to minimize coupling to building floor vibrations.

Section 3. Optical Subsystem Requirements

3.1 The vendor will provide a minimum of one light source operating at 375 nm allowing for minimum feature size of 0.3 micrometers or less. The source must be capable of providing 70 mW or greater of laser power and have an expected lifetime of 8,000 hours or greater.

3.2 Option. The 375 nm optical module must include a minimum of two additional resolution modes having 0.6 micrometer and 0.9 micrometer resolution and automatically controlled by the system software.

3.3 Option. The 375 nm light source must be capable of a 5 micrometer spot size with nominal 40 micrometer depth of focus to allow patterning of thick photoresists.

3.4 The vendor will provide a minimum of one light source operating at 405 nm allowing for minimum feature size of 0.3 micrometers or less. The source must be capable of providing 300 mW or greater of laser power and have an expected lifetime of 10,000 hours or greater.

3.5 Option. The 405 nm optical module must include a minimum of two additional resolution modes having 0.6 micrometer and 0.9 micrometer resolution and automatically controlled by the system software.

3.6 Option. The 405 nm light source must be capable of a 5 micrometer spot size with nominal 40 micrometer depth of focus.

3.7 The optical control system for all wavelengths and spot sizes must support grayscale exposure having minimum of 4096 levels implemented in single‐pass mode.

3.8 The system must provide automatic focus allowing adaptive writing over substrates that are not parallel to x‐y plane of motion.

3.9 Option. The vendor will provide one spare 375 nm light source having 0.3 micrometer or less resolution.

3.10 Option. The vendor will provide one spare 405 nm light source having 0.3 micrometer or less resolution.

Section 4. Computer and CAD requirements.

4.1 The PDWL system will provide controllable light exposure dose of photoresist to customer‐ supplied substrates based on computer aided design (CAD) files to substrates.

4.2 Main system control is to be implemented by a standalone Windows 10 (or later) computer. No server‐client configurations will be considered that require use of non‐DoD information systems.

The vendor will provide both Administrative and User level Windows accounts. The computer must be equipped with LAN connectivity and USB interface for data transfer between other DoD information systems.

4.3 The direct write application must be capable of writing from a variety of CAD file formats including GDS‐II, TIFF, BMP and STL.

4.4 The system application must be capable of implementing write field alignment of patterned structures. Write field alignment is implemented at selected areas within a pattern die by imaging features on the substrate and performing image correlation to reference CAD features and correcting for x, y shift, scale, pattern rotation, and image skew.

Section 5. Training

5.1 Vendor will provide minimum of 1 day of hardware and software training for up to 4 NRL cleanroom personnel.

Section 6. Warranty

6.1

6.2

Vendor will provide a twelve (12) month warranty from the date of Process Acceptance at the

NRL site, including all parts and labor and telephone response during normal business hours with 7 day or less on‐site response to breakdowns. Any required parts to be shipped Priority 1 Day overnight whenever possible.

Option. The vendor will provide extended warranty coverage beyond the initial 1 year warranty.

Acceptance Tests

Tests to evaluate performance will be performed on the unit installed in Building 250, Naval Research

Laboratory. The Building 250 cleanroom facility can provide AZ1500 series (AZ1505) photoresist or similar applied and soft‐baked on a 100 mm DIA silicon wafer. The vendor is allowed to provide their own test substrates. Bottom antireflection coatings (BARCs) may be used. The facility has materials and equipment to perform post‐bake and development steps as needed. Patterns will be evaluated using a

Zeiss Model Gemini 560 scanning electron microscope located in the Building 250 cleanroom.

AT.1. Demonstration of 1:1 line space pattern having critical dimension (CD) of 300 +/‐ 50 nm for both

375 and 405 optical modules.

AT.2 CD uniformity: < 50 nm, for both 375 and 405 nm optical modules.

AT.3 Line Edge Roughness 3‐sigma: < 30 nm, for both 375 and 405 nm optical modules.

AT.4 Overlay accuracy: < 250 nm. A 5 x 25 micrometer center cross will be written atop a 10 x 50 micrometer gold metal center cross pattern on a silicon die and located at the center of 25.4 mm x 25.4 mm die. Four reference 20 x 100 micrometer gold metal cross patterns + 20 micrometer square as shown in Figure 1 will be written using the NRL Raith Voyager e‐beam writing system with laser interferometer stage system and located at four corners of the silicon die with centers located 10 x 10 mm from die center. The mark detection system will be implemented, the 5 x 25 center cross pattern will be written to the photoresist, developed, and analyzed in the Gemini 560 for alignment accuracy.

Figure 1. Alignment pattern to be provided in four corner locations located 10 x 10 mm from die center.

Center cross has dimensions of 20 micrometers width and 100 micrometers length. The square is to be located on the bottom left quadrant with dimensions 10 x 10 micrometers and outer edge collinear to 100 x 100 micrometer field.