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SOFRADIR is widely present on the IR detector market for high-performance space, military and security applications thanks to a well mastered Mercury Cadmium Telluride (MCT) technology, and to the recent acquisition of the III-V InSb, InGaAs, and QWIP technologies. As a result, strong and continuous development efforts are deployed to deliver cutting edge products with improved performances in terms of sensitivity, spatial and thermal resolution. The actual trend in quantum IR detector development is the design of very small pixel, with high operating temperature. The selfconfinement of neighboring diodes may not be efficient enough to maintain optimal modulation transfert function (MTF). This paper presents the recent developments achieved in Sofradir in terms of MTF measurements protocol challenged by the pitch reduction. An overview of state of the art MTF results with optimized measurement technic will be shown, from SWIR to VLWIR MCT focal plane. In order to optimize device performances and reduce development cycle time, this experimental approach has been coupled with finite elements modelisation (FEM). Optimized MTF results for 10µm pitch and HOT MCT technology will be exposed.

Space applications are challenging infrared (IR) technologies, demanding the best system performance achievable. This requires covering the entire IR spectrum from short-wavelength infrared (SWIR) to very long-wavelength infrared (VLWIR) for various pixel sizes, which is possible thanks to a wellmastered mercury cadmium telluride technology. Because of its adjustable gap, it can be operated in all the IR bands. Nevertheless, technology optimization requires deep understanding of physical mechanisms. This paper presents computations by finite-element modeling of two aspects of electrooptical performance: spectral response and modulation transfer function (MTF). Computations and characterizations for all IR bands demonstrate the accuracy of our simulations and the state-of-the-art nature of our technology, which performs according to theory. This paper also highlights the capability to measure MTF at very small pitch (10 lm) by a nondestructive method.

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Sofradir recently presented Daphnis, its latest 10µm pitch XGA and HD720 products. Daphnis XGA is a 10µm pitch 1024x768 mid-wave infrared focal plane array. The development of small pixel pitch is opening the way to very compact products with high spatial resolution. This new product is key contribution to the HOT technology competition allowing reductions in size, weight and power of the overall package. This paper presents the recent developments achieved at Sofradir to make this 10µm pitch HgCdTe focal plane array. Electrical and electro-optical characterizations are presented to define the appropriate design of 10µm pitch diode array. The technological tradeoffs are explained to lower the dark current, to keep high quantum efficiency with a high operability above 110K, F/4.