The Defense Advanced Research Projects Agency (DARPA) Defense Sciences Office (DSO) is inviting submissions of Abstracts for innovative exploratory research concepts in the technical domain of wafer bonding of thin-film crystals under the Crystal Substrate Bonding Technologies and Algorithms (CRYSTAL) Advanced Research Concepts (ARC) Opportunity. This opportunity is issued under the master ARC Exploration Announcement (EA), DARPA-EA-25-02. ARC Opportunities allow individual researchers to focus on paradigm-shifting ideas for national security applications. The effort is expected to be equivalent to one full-time equivalent (FTE) and last for 12 months. The total cost per award should range between $100,000 and $300,000, covering direct and indirect costs, including graduate student tuition, if applicable. Funding for materials, equipment, and Other Direct Costs (ODC) is limited as per DARPA-EA-25-02, and profit will not be authorized. Subawards are not permitted.

The CRYSTAL ARC Opportunity seeks innovative approaches for modeling frameworks to enable predictive wafer bonding processes of thin-film crystals. The goal is to accelerate research and development in multi-functional materials used in sensing and communication technologies, such as integrated quantum, photonic, terahertz (THz), radio frequency (RF), and actuator platforms. Currently, wafer bonding remains highly empirical, requiring extensive experimentation and high costs. This effort aims to develop generalizable models to simulate the bonding of thin-film crystals onto compatible substrates under various process conditions. The focus includes parameters such as bonding temperature, pressure, ion implantation dose, time, and transient gradients of temperature and pressure.

Proposed research should cover two primary phases. In the first 10 months, researchers will develop a bonding model for a multi-functional material-substrate platform of their choice and justify how the model can be generalized for various wafer design parameters. Model validation will be conducted using experimental data, either preliminary or from published sources. In the final two months, the model will be assessed against lithium niobate on insulator (LNOI) bonding and at least one additional material-substrate combination, such as lithium tantalate on insulator, silicon carbide on insulator, yttrium iron garnet on insulator, or gallium nitride on any substrate.

Abstracts must include a substantial technical description outlining the proposed computational approach, its generalizability, and how experimental data will be used for validation. The research plan should include detailed objectives, evaluation measures, and a timeline with monthly and quarterly deliverables. DARPA encourages applicants with or without prior Department of Defense research experience to apply. Abstracts will be evaluated on a rolling basis, with a submission deadline of June 16, 2025, at 4:00 p.m. Eastern Time. Due to limited funding, the Government may shorten the submission period if funding is exhausted.

The application process consists of submitting an Abstract via the DARPA Submission website. If selected, the proposer will be invited to submit an Oral Proposal Package (OPP). The final award will be a Research Other Transaction (OT) agreement under 10 U.S.C. § 4021. No human subjects research is permitted. All technical, contractual, and administrative questions should be directed to CRYSTAL@darpa.mil. Additional resources, including FAQs, are available on SAM.gov under solicitation DARPA-EA-25-02.