Atomic layer deposited Al2O3 passivation of type II InAs/GaSb superlattice photodetectors

Taking advantage of the favorable Gibbs free energies, atomic layer deposited (ALD) aluminum oxide (Al2O3) was used as a novel approach for passivation of type II InAs/GaSb superlattice (SL) midwave infrared (MWIR) single pixel photodetectors in a self cleaning process (λcut-off ∼ 5.1 μm). Al2O3 passivated and unpassivated diodes were compared for their electrical and optical performances. For passivated diodes, the dark current density was improved by an order of magnitude at 77 K. The zero bias responsivity and detectivity was 1.33 A/W and 1.9 × 1013 Jones, respectively at 4 μm and 77 K. Quantum efficiency (QE) was determined as %41 for these detectors. This conformal passivation technique is promising for focal plane array (FPA) applications.

[1]  Yajun Wei,et al.  Passivation of type II InAs/GaSb superlattice photodiodes , 2003 .

[2]  Yajun Wei,et al.  Modeling of type-II InAs/GaSb superlattices using an empirical tight-binding method and interface engineering , 2004 .

[3]  Philippe Christol,et al.  Characterization of midwave infrared InAs/GaSb superlattice photodiode , 2009 .

[4]  Sang Jun Lee,et al.  Electrochemical sulphur passivation of InAs/GaSb strain layer superlattice detectors , 2006 .

[5]  Meimei Z. Tidrow,et al.  Demonstration of midinfrared type-II InAs/GaSb superlattice photodiodes grown on GaAs substrate , 2009 .

[6]  Robert M. Wallace,et al.  GaAs interfacial self-cleaning by atomic layer deposition , 2008 .

[7]  Martin Hjort,et al.  Reduction of native oxides on InAs by atomic layer deposited Al2O3 and HfO2 , 2010 .

[8]  Frank Rutz,et al.  InAs/GaSb superlattices for advanced infrared focal plane arrays , 2009 .

[9]  C. S. Seibert,et al.  Fabrication of midinfrared quantum cascade laser via oxygen-enhanced nonselective wet thermal oxidation , 2011 .

[10]  M. Gendry,et al.  Oxides on GaAs and InAs surfaces: An x-ray-photoelectron-spectroscopy study of reference compounds and thin oxide layers. , 1994, Physical review. B, Condensed matter.

[11]  Christoph H. Grein,et al.  Minority carrier lifetimes in ideal InGaSb/InAs superlattices , 1992 .

[12]  Cory J. Hill,et al.  Atomic scale analysis of the effect of the SiO2 passivation treatment on InAs/GaSb superlattice mesa sidewall , 2008 .

[13]  Mikhail V. Lebedev,et al.  Chalcogenide passivation of III–V semiconductor surfaces , 1998 .

[14]  J. B. Rodriguez,et al.  Mid-IR focal plane array based on type-II InAs /GaSb strain layer superlattice detector with nBn design , 2008 .

[15]  H. Iwai,et al.  Electrical Characterization of $\hbox{Al}_{2} \hbox{O}_{3}$/n-InAs Metal–Oxide–Semiconductor Capacitors With Various Surface Treatments , 2011, IEEE Electron Device Letters.

[16]  Arezou Khoshakhlagh,et al.  Performance improvement of InAs/GaSb strained layer superlattice detectors by reducing surface leakage currents with SU-8 passivation , 2010 .

[17]  Yajun Wei,et al.  Near bulk-limited R0A of long-wavelength infrared type-II InAs/GaSb superlattice photodiodes with polyimide surface passivation , 2007 .

[18]  Yan-Kai Chiou,et al.  Interfacial self-cleaning in atomic layer deposition of HfO2 gate dielectric on In0.15Ga0.85As , 2006 .

[19]  Manijeh Razeghi,et al.  Surface leakage reduction in narrow band gap type-II antimonide-based superlattice photodiodes , 2009 .

[20]  Suman Datta,et al.  Fermi level unpinning of GaSb (100) using plasma enhanced atomic layer deposition of Al2O3 , 2010 .

[21]  Daryl Pulver,et al.  Thermal oxides of In0.5Ga0.5P and In0.5Al0.5P , 2001 .

[22]  Martin Walther,et al.  Passivation of InAs∕(GaIn)Sb short-period superlattice photodiodes with 10μm cutoff wavelength by epitaxial overgrowth with AlxGa1−xAsySb1−y , 2005 .

[23]  Darryl L. Smith,et al.  Proposal for strained type II superlattice infrared detectors , 1987 .