Fabrication of InAs photodiodes with reduced surface leakage current

Andrew R. J. Marshall; Chee Hing Tan; John P. R. David; Jo Shien Ng; Mark Hopkinson

doi:10.1117/12.740700

16 October 2007 Fabrication of InAs photodiodes with reduced surface leakage current

Andrew R. J. Marshall, Chee Hing Tan, John P. R. David, Jo Shien Ng, Mark Hopkinson

Proceedings Volume 6740, Optical Materials in Defence Systems Technology IV; 67400H (2007) https://doi.org/10.1117/12.740700
Event: Optics/Photonics in Security and Defence, 2007, Florence, Italy

Abstract

We report the findings of work undertaken to develop InAs photodiodes with low reverse leakage current, for detection of mid-wave infrared wavelengths up to 3.5μm. Good quality epitaxial growth of InAs and the lattice matched ternary AlAs_0.16Sb_0.84 was developed using molecular beam epitaxy. A photodiode structure was designed, grown and characterized using an AlAs_0.16Sb_0.84 layer to block the diffusion of minority electrons. Further reductions in the reverse leakage current were achieved through studies of wet etching using a range of etchants. A sulphuric acid based etchant provided the lowest surface leakage current for a single etch step, however the surface leakage current was further reduces when a two steps etching process was employed, starting with a phosphoric acid based etchant and finishing off with a sulphuric acid based etchant. Surface profile analysis showed that higher etching rates were obtained in the direction parallel to the <100> direction. The atomic composition of the etched surface was investigated using Auger analysis. By etching a test pixel array, the potential for fabricating small pitch focal plane arrays by wet etching was evaluated.

Citation Download Citation

Andrew R. J. Marshall, Chee Hing Tan, John P. R. David, Jo Shien Ng, and Mark Hopkinson "Fabrication of InAs photodiodes with reduced surface leakage current", Proc. SPIE 6740, Optical Materials in Defence Systems Technology IV, 67400H (16 October 2007); https://doi.org/10.1117/12.740700

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available