He was elected as a corresponding member (2004) and next as an ordinary member (2013) of the Polish Academy of Sciences. In June 2015 was appointed as a dean of Division IV Polish Academy of Sciences: Engineering Sciences.
Professor Rogalski has given above 70 invited plenary talks (keynote speech) at international conferences. He is author and co-author of about 280 indexed papers, cited ca. from 6300 to 12000 with h-index from 35 to 48 in dependence on scientific base (Web of Science, Scopus, Google Scholar), 13 books (7 books was published by SPIE Publisher), and 37 monographic papers (book chapters in handbooks and encyclopedias).
In this paper fundamental physical properties of two material systems, HgCdTe and T2SLs, are compared together with their influence on detector performance: dark current density, RA product, quantum efficiency, and noise equivalent different temperature. In comparison with HgCdTe, fundamental properties of T2SLs are inferior. On the other hand, T2SL and barrier detectors have several advantages to include lower tunnelling and surface leakage currents, and suppressed Auger recombination mechanism. Up to date, the promise of superior performance of these detectors has not been realized yet. In the paper we present that the performance of T2SL detectors (dark current, current responsivity, and noise equivalent difference temperature) is lower than bulk HgCdTe photodiodes.
Due to stronger, less ionic chemical bonding of III-V semiconductors, these materials are attractive due to manufacturability and stability. It is also predicted that the interband T2SL quantum cascade devices will outperform the performance of the high operating temperature HgCdTe detectors.
The sophisticated physics associated with the antimonide-based bandgap engineering will give a new impact and interest in development of infrared detector structures. Important advantage of T2SLs is the high quality, high uniformity and stable nature of the material. In general, III-V semiconductors are more robust than their II-VI counterparts due to stronger, less ionic chemical bonding. As a result, III-V-based FPAs excel in operability, spatial uniformity, temporal stability, scalability, producibility, and affordability – the so-called “ibility” advantages.
In well established uncooled imaging, microbolometer arrays are clearly the most used technology. The microbolometer detectors are now produced in larger volumes than all other IR array technologies together. Present state-of-the-art microbolometers are based on polycrystalline or amorphous materials, typically vanadium oxide (VOx) or amorphous silicon (a-Si), with only modest temperature sensitivity and noise properties. Basic efforts today are mainly focused on pixel reduction and performance enhancement.
Due to less ionic chemical bonding, III-V semiconductors are more robust than their II-VI counterparts. As a result, III-V-based FPAs excel in operability, spatial uniformity, temporal stability, scalability, producibility, and affordability – the so-called “ibility” advantages.
Based on these promising results it is obvious now that the InAs/GaSb superlattice technology is competing with HgCdTe third generation detector technology with the potential advantage of standard III-V technology to be more competitive in costs and as a consequence series production pricing. Comments to the statement whether the superlattice IR photodetectors can outperform the “bulk” narrow gap HgCdTe detectors is one of the most important questions for the future of IR photodetectors presented by Rogalski at the April 2006 SPIE meeting in Orlando, Florida, are more credible today and are presented in this paper. It concerns the trade-offs between two most competing IR material technologies: InAs/GaSb type-II superlattices and HgCdTe ternary alloy system.
Recently, a new strategy used to achieve high operation temperature (HOT) infrared photodetectors including cascade devices and alternate materials such as type-II superlattices has been observed. Another method to reduce detector’s dark current is reducing volume of detector material via a concept of photon trapping detector.
In this paper, the performance of a novel HOT detector designing so-called interband cascade type-II MWIR InAs/GaSb superlattice detectors is presented. Detailed analysis of the detector’s performance (such as dark current, RA product, current responsivity, and response time) versus bias voltage and operating temperatures (220 – 400 K) is performed pointing out optimal working conditions. At present stage of technology, the experimentally measured R0A values of interband cascade type-II superlattice detectors at room temperature are higher than those predicted for HgCdTe photodiodes. It is shown that these novel HOT detectors have emerged as competitors of HgCdTe photodetectors.
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