Midwave infrared InAs/GaSb superlattice photodiode with a dopant-free p–n junction

Midwave infrared (MWIR) InAs/GaSb superlattice (SL) photodiode with a dopant-free p–n junction was fabricated by molecular beam epitaxy on GaSb substrate. Depending on the thickness ratio between InAs and GaSb layers in the SL period, the residual background carriers of this adjustable material can be either n-type or p-type. Using this flexibility in residual doping of the SL material, the p–n junction of the device is made with different non-intentionally doped (nid) SL structures. The SL photodiode processed shows a cut-off wavelength at 4.65 μm at 77 K, residual carrier concentration equal to 1.75 × 1015 cm−3, dark current density as low as 2.8 × 10−8 A/cm2 at 50 mV reverse bias and R0A product as high as 2 × 106 Ω cm2. The results obtained demonstrate the possibility to fabricate a SL pin photodiode without intentional doping the pn junction

Radiometric and noise characteristics of InAs-rich T2SL MWIR pin photodiodes

We present a full characterization of the radiometric performances of a type-II InAs/GaSb superlattice pin photodiode operating in the mid-wavelength infrared domain. We first focused our attention on quantum efficiency, responsivity and angular response measurements: quantum efficiency reaches 23% at λ = 2.1 µm for 1 µm thick structure. Noise under illumination measurements are also reported: noise is limited by the Schottky contribution for reverse bias voltage smaller than 1.2 V. The specific detectivity, estimated for 2p field-of-view and 333 K background temperature, was determined equal to 2.29 x 10^10 Jones for -0,8 V bias voltage and 77 K operating temperature

Estimating the Incidence of Typhoid Fever and Other Febrile Illnesses in Developing Countries

To measure the incidence of typhoid fever and other febrile illnesses in Bilbeis District, Egypt, we conducted a household survey to determine patterns of health seeking among persons with fever. Then we established surveillance for 4 months among a representative sample of health providers who saw febrile patients. Health providers collected epidemiologic information and blood (for culture and serologic testing) from eligible patients. After adjusting for the provider sampling scheme, test sensitivity, and seasonality, we estimated that the incidence of typhoid fever was 13/100,000 persons per year and the incidence of brucellosis was 18/100,000 persons per year in the district. This surveillance tool could have wide applications for surveillance for febrile illness in developing countries

Influence of the GaSb layer thickness on the properties of InAs/GaSb SL photodiodes

International audienc

InAs/GaSb superlattice pin photodiode: choice of the SL period to enhance the temperature operation in the MWIR domain

International audienc

Comparison of the electro-optical performances of symmetrical and asymmetrical MWIR InAs/GaSb superlattice pin photodiodes

International audienc

Comparison of the electro-optical performance of MWIR InAs/GaSb superlattice pin photodiodes and FPA with asymmetrical designs

International audienc

Noise measurements for the performance analysis of infrared photodetectors

International audienc