Complex Defense systems, such as RADAR, communications, imaging and sensing systems rely on a wide variety of microsystems devices and materials. These diverse devices and materials typically require different substrates and different processing technologies, preventing the integration of these devices into single fabrication process flows. Thus, integration of these device technologies has historically occurred only at the chip-to-chip level, which introduces significant bandwidth and latency-related performance limitations on these systems, as well as increased size, weight, power, and packaging/assembly costs as compared to microsystems fully integrated on a single chip.

The DAHI program is developing transistor-scale heterogeneous integration processes to intimately combine advanced compound semiconductor (CS) devices, as well as other emerging materials and devices, with high-density silicon complementary metal-oxide-semiconductor (CMOS) technology. The ultimate goal of DAHI is to establish a manufacturable, accessible foundry technology for the monolithic heterogeneous co-integration of diverse devices and complex silicon-enabled architectures on a common substrate platform. Such integration would increase the capabilities of high-performance microsystems for the U.S. Military. The DAHI program will address the following key technical challenges (1) heterogeneous integration process development, (2) high-yield manufacturing and foundry establishment, and (3) circuit design and architecture innovation.

Microsystem devices and materials that may be integrated include:

Silicon complementary metal-oxide-semiconductor (Si CMOS) for highly integrated analog and digital circuits

Gallium Nitride (GaN) for high-power/high-voltage swing and low-noise amplifiers

Gallium Arsenide (GaAs) and Indium Phosphide (InP) heterojunction bipolar transistors (HBT) and high-electron mobility transistors (HEMT) for high speed/high-dynamic-range/low-noise circuits

Antimonide-based compound semiconductors for high-speed, low-power electronics

Compound semiconductor optoelectronic devices for direct-bandgap photonic sources and detectors, as well as or silicon-based structures for modulators, waveguides, etc.

Microelectromechanical (MEMS) components for sensors, actuators and RF resonators

Thermal management structures

DARPA’s efforts in heterogeneous integration began with the Compound Semiconductor Materials on Silicon (COSMOS) program. COSMOS is now a DAHI program thrust, along with Electronic-Photonic Heterogeneous Integration (E-PHI) and DAHI Foundry Technology thrusts.