Electronics, Army STTR, Phase I
Aluminum Nitride-Based Monolithic Microwave Integrated Circuits
Objective
Businesses must develop an aluminum nitride-based platform for monolithic microwave integrated circuits used in extreme-radio-frequency and high-power operations.
Description
The next generation of devices and systems for electronic microwave applications need to offer high frequencies, high power, compactness, high performance and high temperature operation. Several materials platforms such as silicon carbide (SiC), gallium arsenide (GaAs), silicon (Si) and aluminum nitride (AlN) compete for market share in this emerging high frequency applications sector.
Among them, AlN stands out as an exceptional material for next-generation monolithic microwave integrated circuits (MMICs). It offers a multitude of advantages paramount for advanced electronic systems. These include its ultrawide and direct bandgap (6.2 eV), large critical electric field (15 MV/cm) and high thermal conductivity (∼340 W/mK). This allows for efficient heat dissipation, which is critical in maintaining high power operations and the reliability of high-frequency circuits.
Current research and development focuses on gallium nitride (GaN) and aluminum gallium nitride (AlGaN) high electron mobility transistors (HEMTs) for operations requiring both high power and high frequency. This has led to the demonstration of the state-of-the-art GaN HEMTs that offer output power of up to 8.84 W/mm at up to 94 GHz. However, the GaN HEMTs were fabricated on SiC substrates. AlN’s compatibility with GaN and AlGaN HEMTs facilitates seamless integration and avoids the lattice mismatch issues encountered in SiC substrates.
This would enable the development of compact, high-frequency devices with superior operational capabilities. Additionally, the current availability of insulating a large, AlN of high substrate quality ensures the precise and reliable MMIC fabrication as well as unwanted electrical interactions. This enhances signal integrity at high frequencies.
However, despite these advantages, research and development of AlN-based MMICs remain in their infancy. This requires more effort to fully harness its capabilities. The utilization of high-purity, semi-insulating AlN as a substrate for MMICs also requires precise knowledge of materials properties of AlN at millimeter-wave frequencies (such as electrical permittivities) to accurately predict the propagation delay and attenuation of waves along the transmission lines.
The Army wants to leverage recent achievements in AlN and AlGaN and create commercializable AlN-based MMICs that outperform current state-of-the-art GaN MMICs for higher power/frequency applications. The needed work includes fundamental research and development to establish materials properties and fabrication routes for AlN-based devices.
This would require the design and fabrication of resonators for microwave or RF circuits via closed loops, circular waveguides or transmission lines to allow for resonance at specific microwave frequencies. The developed resonators could extract fundamental materials properties such as permittivity and loss tangent.
Subsequently, the Army needs to pursue a route towards integration of the developed resonators with typical electronic components to focus on the proposer’s defined application. The Army anticipates a fully integrated microwave circuit that the vendor must present as a prototype.
Phase I
In phase I, the selectee will describe a few important Army-relevant applications for AlN-based MMICs and select the particular application they wish to address. Using this application as a testbed, businesses must design and fabricate AlN-based microwave/mmWave resonators.
The fabricated resonators should extract the substrate’s frequency-dependent material properties up to W band (i.e., 1 to 75 GHz). This information should then help design, fabricate and test transmission lines with a return loss of < 10 dB and insertion loss < 0.6 dB/mm up to 75 GHz. At the end of Phase I, the feasibility of AlN-based MMICs should receive an assessment. With the growing demand for high frequency and high power MMICs for military and civilian applications, mmWave MMICs based on AlN projects strong commercialization potential.
Phase II
During Phase II, the selectee will design, fabricate and characterize the AlN-based resonators to obtain frequency-dependent material parameters up to 170 GHz. The performer must demonstrate a process for substrate thinning to a thickness of 100 µm or smaller.
Additionally, the vendor must deomstrate through substrate vias (TSV) with a diameter less than 100 µm. This will result in the design, fabrication and characterization of low-loss waveguides and waveguide transitions with demonstrations in the W and D bands. The peak return loss and average insertion loss should be <18 dB and <0.5 dB/mm, respectively, up to 170 GHz.
In order to demonstrate the feasibility of AlN-based MMICs, the selectee will integrate the waveguides with an electronic element aligned with the proposed application, such as an amplifier, mixer, oscillator or switch. At the end of Phase II, the selectee should demonstrate that the developed systems address limitations of current systems for the chosen application.
The selectee should thoroughly investigate the commercial transition potential of AlN-based MMICs. Given their potential to significantly advance high-frequency electronics, the Army encourages the selectee to explore this avenue and potentially position themselves as a key player in industries such as telecommunications, aerospace and defense.
Phase III
During the Phase III approach, the vendor should continue the work from Phase II. Here, the vendor must focus on the development of a truly integrated MMIC. The selectee should undertake reliability testing/qualification and produce a process design kit.
Moreover, the business must explore the potential to transfer the technology to military systems (e.g., radar, electronic warfare and communication) and civilian applications. The selectee should work with Army primes and industry partners to commercialize the technology via a trusted foundry and to provide technology availability to the defense and military markets.
Submission Information
All eligible businesses must submit proposals by noon ET.
To view full solicitation details, click here.
For more information, and to submit your full proposal package, visit the DSIP Portal.
STTR Help Desk: usarmy.rtp.devcom-arl.mbx.sttr-pmo@army.mil
References:
- Hickman, A. L., Chaudhuri, R., Bader S. J., Nomoto, K., Li, L., Hwang, J. C. M., Xing, H. G., and Jena, D. “Next generation electronics on the ultrawide-bandgap aluminum nitride platform.” Semicond. Sci. Technol. 36 044001 (2021). https://doi.org/10.1088/1361-6641/abe5fd;
- Li, L., Reyes, S., Asadi, M.J., Fay, P., Hwang, J.C.M. “Extraordinary permittivity characterization of 4H SiC at millimeter-wave frequencies”. Applied Physics Letters 123, 012105 (2023). https://doi.org/10.1063/5.0148623;
- Singhal, J., Chaudhuri, R., Hickman, A., Protasenko, V., Xing, H. G., Jena, D. “Toward AlGaN channel HEMPTs on AlN: Polarization-induced 2DEGs in AlN/AlGaN/AlN heterostructures”. Applied Physics Letters Materials 10, 111120 (2022). https://doi.org/10.1063/5.0121195;
- Schwantuschke, D., Godejohann B. J., Brückner, P., Tessmann, A., and Quay, R. “mm-Wave operation of AlN/GaN-devices and MMICs at V- & W-band”. 22nd International Microwave and Radar Conference (MIKON), Poznan, Poland, pp. 238-241 (2018). doi: 10.23919/MIKON.2018.8405187. https://ieeexplore.ieee.org/document/8405187;
- Collazo R., Sitar Z., High n-type conductivity and carrier concentration in Si-implanted homoepitaxial AlN, Applied Physics Letters 118, 112104 (2021). https://doi.org/10.1063/5.0042857;
- Doolittle, W.A., Matthews, C.M., Ahmad, H., Motoki, K., Lee, S., Ghosh, A., Marshall, E. N., Tang, A. L., Manocha, P., Yoder, P. D., “Prospectives for AlN electronics and optoelectronics and the important role of alternative synthesis”. Applied Physics Letters 123, 070501 (2023). https://doi.org/10.1063/5.0156691;
- Ahmad, H., Lindemuth, J., Engel, Z., Matthews, C. M., Motoki, K., Doolittle, W. A., “Substantial p-type Conductivity of AlN Achieved via Beryllium Doping”, Advanced Materials 33, 2104497 (2021). https://doi.org/10.1002/adma.202104497;
- Romanczyk, B., Zeng, X., Guidry, M., Li, H., Hatui, N., Wurm, C., Hrishna, A., Ahmadi, E., Keller, S., and Mishra, U. K., “W-Band Power Performance of SiN-Passivated N-Polar GaN Deep Recess HEMTs”. IEEE Electron Device Letters, 41 (3), 349-352 (2020). 10.1109/LED.2020.2967034
- Aluminum Nitride, MMICs, Ultra-Wide Bandgap, High Frequency, Microwave, mmWAve
Objective
Businesses must develop an aluminum nitride-based platform for monolithic microwave integrated circuits used in extreme-radio-frequency and high-power operations.
Description
The next generation of devices and systems for electronic microwave applications need to offer high frequencies, high power, compactness, high performance and high temperature operation. Several materials platforms such as silicon carbide (SiC), gallium arsenide (GaAs), silicon (Si) and aluminum nitride (AlN) compete for market share in this emerging high frequency applications sector.
Among them, AlN stands out as an exceptional material for next-generation monolithic microwave integrated circuits (MMICs). It offers a multitude of advantages paramount for advanced electronic systems. These include its ultrawide and direct bandgap (6.2 eV), large critical electric field (15 MV/cm) and high thermal conductivity (∼340 W/mK). This allows for efficient heat dissipation, which is critical in maintaining high power operations and the reliability of high-frequency circuits.
Current research and development focuses on gallium nitride (GaN) and aluminum gallium nitride (AlGaN) high electron mobility transistors (HEMTs) for operations requiring both high power and high frequency. This has led to the demonstration of the state-of-the-art GaN HEMTs that offer output power of up to 8.84 W/mm at up to 94 GHz. However, the GaN HEMTs were fabricated on SiC substrates. AlN’s compatibility with GaN and AlGaN HEMTs facilitates seamless integration and avoids the lattice mismatch issues encountered in SiC substrates.
This would enable the development of compact, high-frequency devices with superior operational capabilities. Additionally, the current availability of insulating a large, AlN of high substrate quality ensures the precise and reliable MMIC fabrication as well as unwanted electrical interactions. This enhances signal integrity at high frequencies.
However, despite these advantages, research and development of AlN-based MMICs remain in their infancy. This requires more effort to fully harness its capabilities. The utilization of high-purity, semi-insulating AlN as a substrate for MMICs also requires precise knowledge of materials properties of AlN at millimeter-wave frequencies (such as electrical permittivities) to accurately predict the propagation delay and attenuation of waves along the transmission lines.
The Army wants to leverage recent achievements in AlN and AlGaN and create commercializable AlN-based MMICs that outperform current state-of-the-art GaN MMICs for higher power/frequency applications. The needed work includes fundamental research and development to establish materials properties and fabrication routes for AlN-based devices.
This would require the design and fabrication of resonators for microwave or RF circuits via closed loops, circular waveguides or transmission lines to allow for resonance at specific microwave frequencies. The developed resonators could extract fundamental materials properties such as permittivity and loss tangent.
Subsequently, the Army needs to pursue a route towards integration of the developed resonators with typical electronic components to focus on the proposer’s defined application. The Army anticipates a fully integrated microwave circuit that the vendor must present as a prototype.
Phase I
In phase I, the selectee will describe a few important Army-relevant applications for AlN-based MMICs and select the particular application they wish to address. Using this application as a testbed, businesses must design and fabricate AlN-based microwave/mmWave resonators.
The fabricated resonators should extract the substrate’s frequency-dependent material properties up to W band (i.e., 1 to 75 GHz). This information should then help design, fabricate and test transmission lines with a return loss of < 10 dB and insertion loss < 0.6 dB/mm up to 75 GHz. At the end of Phase I, the feasibility of AlN-based MMICs should receive an assessment. With the growing demand for high frequency and high power MMICs for military and civilian applications, mmWave MMICs based on AlN projects strong commercialization potential.
Phase II
During Phase II, the selectee will design, fabricate and characterize the AlN-based resonators to obtain frequency-dependent material parameters up to 170 GHz. The performer must demonstrate a process for substrate thinning to a thickness of 100 µm or smaller.
Additionally, the vendor must deomstrate through substrate vias (TSV) with a diameter less than 100 µm. This will result in the design, fabrication and characterization of low-loss waveguides and waveguide transitions with demonstrations in the W and D bands. The peak return loss and average insertion loss should be <18 dB and <0.5 dB/mm, respectively, up to 170 GHz.
In order to demonstrate the feasibility of AlN-based MMICs, the selectee will integrate the waveguides with an electronic element aligned with the proposed application, such as an amplifier, mixer, oscillator or switch. At the end of Phase II, the selectee should demonstrate that the developed systems address limitations of current systems for the chosen application.
The selectee should thoroughly investigate the commercial transition potential of AlN-based MMICs. Given their potential to significantly advance high-frequency electronics, the Army encourages the selectee to explore this avenue and potentially position themselves as a key player in industries such as telecommunications, aerospace and defense.
Phase III
During the Phase III approach, the vendor should continue the work from Phase II. Here, the vendor must focus on the development of a truly integrated MMIC. The selectee should undertake reliability testing/qualification and produce a process design kit.
Moreover, the business must explore the potential to transfer the technology to military systems (e.g., radar, electronic warfare and communication) and civilian applications. The selectee should work with Army primes and industry partners to commercialize the technology via a trusted foundry and to provide technology availability to the defense and military markets.
Submission Information
All eligible businesses must submit proposals by noon ET.
To view full solicitation details, click here.
For more information, and to submit your full proposal package, visit the DSIP Portal.
STTR Help Desk: usarmy.rtp.devcom-arl.mbx.sttr-pmo@army.mil
References:
- Hickman, A. L., Chaudhuri, R., Bader S. J., Nomoto, K., Li, L., Hwang, J. C. M., Xing, H. G., and Jena, D. “Next generation electronics on the ultrawide-bandgap aluminum nitride platform.” Semicond. Sci. Technol. 36 044001 (2021). https://doi.org/10.1088/1361-6641/abe5fd;
- Li, L., Reyes, S., Asadi, M.J., Fay, P., Hwang, J.C.M. “Extraordinary permittivity characterization of 4H SiC at millimeter-wave frequencies”. Applied Physics Letters 123, 012105 (2023). https://doi.org/10.1063/5.0148623;
- Singhal, J., Chaudhuri, R., Hickman, A., Protasenko, V., Xing, H. G., Jena, D. “Toward AlGaN channel HEMPTs on AlN: Polarization-induced 2DEGs in AlN/AlGaN/AlN heterostructures”. Applied Physics Letters Materials 10, 111120 (2022). https://doi.org/10.1063/5.0121195;
- Schwantuschke, D., Godejohann B. J., Brückner, P., Tessmann, A., and Quay, R. “mm-Wave operation of AlN/GaN-devices and MMICs at V- & W-band”. 22nd International Microwave and Radar Conference (MIKON), Poznan, Poland, pp. 238-241 (2018). doi: 10.23919/MIKON.2018.8405187. https://ieeexplore.ieee.org/document/8405187;
- Collazo R., Sitar Z., High n-type conductivity and carrier concentration in Si-implanted homoepitaxial AlN, Applied Physics Letters 118, 112104 (2021). https://doi.org/10.1063/5.0042857;
- Doolittle, W.A., Matthews, C.M., Ahmad, H., Motoki, K., Lee, S., Ghosh, A., Marshall, E. N., Tang, A. L., Manocha, P., Yoder, P. D., “Prospectives for AlN electronics and optoelectronics and the important role of alternative synthesis”. Applied Physics Letters 123, 070501 (2023). https://doi.org/10.1063/5.0156691;
- Ahmad, H., Lindemuth, J., Engel, Z., Matthews, C. M., Motoki, K., Doolittle, W. A., “Substantial p-type Conductivity of AlN Achieved via Beryllium Doping”, Advanced Materials 33, 2104497 (2021). https://doi.org/10.1002/adma.202104497;
- Romanczyk, B., Zeng, X., Guidry, M., Li, H., Hatui, N., Wurm, C., Hrishna, A., Ahmadi, E., Keller, S., and Mishra, U. K., “W-Band Power Performance of SiN-Passivated N-Polar GaN Deep Recess HEMTs”. IEEE Electron Device Letters, 41 (3), 349-352 (2020). 10.1109/LED.2020.2967034
- Aluminum Nitride, MMICs, Ultra-Wide Bandgap, High Frequency, Microwave, mmWAve