Nuclear Physics Electronics Design and Fabrication

DOE nuclear imaging research requires large detector arrays and highly segmented detector electrode geometries. These designs are difficult to implement with available packaging and interconnect methods. There is a need for low-cost, reliable electronic interconnect fabrication tools with capability to build sophisticated geometries from the microelectronics level to large detector array scale. Our Localized Laser Chemical Vapor Deposition CVD) technique meets these requirements because it can deposit material layers with consistent dimensions, strong bonding strength, and various packaging geometries including planar and curved surfaces. This capability ensures production of stable electrical components with consistent circuit performance. The technique can fabricate multiple layers from different materials simultaneously by switching chemical precursors, and can be scaled to connect signals of different packaging dimensions, such as from dense large array signal paths to CMOS circuit connection with detector pixels. Our proposed Phase I R&D objective is to demonstrate the feasibility of using localized laser Chemical Vapor Deposition CVD) to print interconnection materials between circuits and electronic components on different substrates and surface geometries. During Phase I we will modify our existing laser CVD design for large scale sensor application requirements and demonstrate 3D additive printing on planar silicon wafers and curvedsubstrates. We will also investigate printing on vertical surfaces through laser source orientation adjustment, and define design requirements for integrating the tool with robotic positioners. Phase II will produce a commercially viable prototype Laser CVD and methodology capable of printing conductive materials to interconnect high-density front-end CMOS circuits with silicon detector layers for large scale detector array construction. We have successfully demonstrated electrical circuit fabrication in our prototype laser CVD chamber. This work was performed under a DoD SBIR Phase I seeking additive manufacturing methods for building conformal 3D) circuits at various integration scales. We are commercializing this technology through corporate funds andpatents. Our Phase I proposal briefly describes Laser CVD and how it may solve the DOE requirement for large detector array integration, along with a detailed work plan for demonstrating conformal interconnect fabrication. Dr. Zhigang Xiao, the PI for this project and founder of Microcvd Corporation, has over 20 years experiences in both CVD and ink jet printing product development. The Microcvd engineering staff has the required expertise in vapor deposition and optical engineering for modifying our CVD prototype to demonstrate conformal, multi-scale interconnection of large array electronics. This Phase I work will result in design requirements and development plan for the Phase II commercial product prototype.