OBJECTIVE: Reduce the cost and improve manufacturability of high-power Quantum Cascade Lasers (QCLs) by 10 times.

 

DESCRIPTION: QCLs are monolithic semiconductor chips that produce mid-infrared laser light (4-12 microns wavelength range) used for directed infrared countermeasures (DIRCM), laser detection and ranging (LIDAR), and remote molecular detection. They are complex, multi-layer semiconductor structures (500-1000 layers) that demand high controllability of the material growth rate and composition [Refs 1, 2]. Current high-power QCLs (=1W) cost in the range of $10,000 each, which makes the adoption of this technology cost prohibitive for many applications, especially those that require a large number of lasers. Further development is needed to obtain a substantial (>10X) reduction in manufacturing costs for high-power QCL.

 

The program should address the 3 key process steps that add significant costs to QCL manufacturing: base growth, regrowth, and assembly.

1.   Optimize the uniformity and repeatability of the growth of QCL base material on larger size (greater than 3 in. diameter) wafers using high-volume (greater than 10 wafers in one batch) metal organic chemical vapor deposition (MOCVD) reactors to gain the economies of scale. The laser emission wavelength variation among all wafers in the same batch should be no more than +/- 1.5%, and the laser emission wavelength variation across each wafer within the same batch should not be more than +/- 1.5%. This capability would enable cost-effective stockpiling of qualified laser material at the wafer level.

2.   Improve the epitaxial regrowth of insulating Fe-doped InP to form buried heterostructure lasers using Regrowth by 95%. Normally this is performed with MOCVD, which is the lowest-yielding processing step in the fabrication of buried heterostructure QCLs. The expected improved yield on this regrowth process is to exceed 95%.

3.   QCLs require expensive high thermal conductivity packaging [Ref 3]. Thus, low chip yields lead to high packaged device cost. High yield at this stage is crucial, as the product has incurred the full cost of fabrication. The overall expected chip yield from growth to pre-packaging via the improved manufacturing process is to exceed 92%.

 

PHASE I: Develop and design an innovative manufacturing process and provide the related cost analysis. Demonstrate the feasibility of the proposed process. Ensure the manufacturing plan meets the specification in the Description. The Phase I effort will include prototype plans to be developed under Phase II.

 

PHASE II: Further develop the full wafer, high yield single-mode QCL manufacturing process. Demonstrate that it achieves a factor of 10x reduction in cost. It is expected that the proposers will produce 100 QCL diodes in order to prove the developed process.

 

PHASE III DUAL USE APPLICATIONS: Finalize and transition the high performance QCLs with substantial manufacturing cost reduction based on the methodology attained from Phase II for applications in the areas of DIRCM, advanced chemicals sensors and LIDARs.

 

The commercial sector could benefit from this crucial, game-changing, low-cost technology development in the areas of detection of toxic gases, environmental pollution monitoring, and non-invasive health monitoring and sensing. Gas and oil companies, and first responders would benefit.

 

REFERENCES:

1.   Wang, C., Schwarz, B., Siriani, D., Missaggia, L., Connors, M., Mansuripu, T., and Capasso, F. �MOVPE Growth of LWIR AlnAs/GalnAs/InP Quantum Cascade Lasers: Impact of Growth and Material Quality on Laser Performance.� IEEE Journal of Selected Topics in Quantum Electronics, 2017. https://ieeexplore.ieee.org/document/7870635/authors#authors

 

2.   Shin, J., Mawst, L., & Botez, D. �Crystal Growth via Metal-Organic Vapor Phase Epitaxy of Quantum-Cascade- Laser Structures Composed of Multiple Alloy Compositions.� Journal of Crystal Growth, Volume 357, 15 October 2012, pp. 15-19. https://www.sciencedirect.com/science/article/pii/S0022024812004988

 

3.   Barletta, P., Diehl, L., North, M., Yang, B., Baldasaro, N., & Temple, D. �Advanced Thermal Management of High-Power Quantum Cascade Laser Arrays for Infrared Countermeasures.� Proceedings Volume 10435,