High-quality large-area MBE HgCdTe/Si

• Published in: Journal of electronic materials 2006-06, Vol.35 (6), p.1283-1286
• Main Authors: PETERSON, J. M, FRANKLIN, J. A, REDDY, M, JOHNSON, S. M, SMITH, E, RADFORD, W. A, KASAI, I
• Format: Article
• Language: English
• Subjects: Advantages; Cross-disciplinary physics: materials science; rheology; Defects; Density; Exact sciences and technology; Fourier transforms; Indium; Infrared radiation; Mass spectrometry; Materials science; Mercury cadmium telluride; Methods of deposition of films and coatings; film growth and epitaxy; Molecular, atomic, ion, and chemical beam epitaxy; Physics; Silicon wafers; Substrates; Vision systems
• ISSN: 0361-5235; 1543-186X
• DOI: 10.1007/s11664-006-0255-1

HgCdTe offers significant advantages over other similar semiconductors, which has made it the most widely utilized variable-gap material in infrared (IR) focal plane array (FPA) technology. HgCdTe hybrid FPAs consisting of two-dimensional detector arrays that are hybridized to Si readout circuits (ROIC) are the dominant technology for second-generation infrared systems. However, one of the main limitations of the HgCdTe materials system has been the size of lattice-matched bulk CdZnTe substrates, used for epitaxially grown HgCdTe, which have been limited to 30 cm^sup 2^ in production. This size limitation does not adequately support the increasing demand for larger FPA formats which now require sizes up to 2048 × 2048, and only a single die can be printed per wafer. Heteroepitaxial Si-based substrates offer a cost-effective technology that can be scaled to large wafer sizes and further offer a thermal-expansion-matched hybrid structure that is suitable for large format FPAs. This paper presents data on molecular-beam epitaxy (MBE)-grown HgCdTe/Si wafers with much improved materials characteristics than previously reported. We will present data on 4- and 6-in diameter HgCdTe both with extremely uniform composition and extremely low defects. Large-diameter HgCdTe/Si with nearly perfect compositional uniformity and ultra low defect density is essential for meeting the demanding specifications of large format FPAs. [PUBLICATION ABSTRACT]