Low frequency noise in reverse biased P-InAsSbP/n-InAs infrared photodiodes

Abstract

We report the first experimental study of low-frequency noise in reverse biased P-InAsSbP/n-InAs infrared photodiodes at 300 K and 77 K. At room temperature, the current noise spectral density, S I , depends on frequency as 1/f over the entire current range and tends to the Nyquist noise when the frequency increases. At small reverse currents I rb 3×10 −5 A, S I is proportional to I ; rb 2 at higher currents this dependence changes to S I ∼I . rb 4 With temperature decrease down to 77 K, S I becomes proportional to I , rb 0.5 while the reverse current decreases and the differential resistance grows by 4 orders of magnitude. The noise was also studied in the photovoltaic mode at 100 K, where S I is proportional to I . ph 2We conclude that at 100 K, the Nyquist noise is dominant and can be used for estimations of the specific detectivity of P-InAsSbP/n-InAs diodes.

Room temperature low frequency noise in n+-InAs/n-InAsSbP/InAs/p-InAsSbP double heterostructure infrared photodiodes

“…Under illumination, the spectral noise density S is proportional to I 2 while under forward bias it is proportional to I 1. 5 .…”

“…The InAsSbP/InAs heterostructure photodiodes (PDs), e.g. single heterostructure (SH) PDs, are also good candidates for mid-IR detection with BLIP temperature as high as 180 K [4] and room temperature Johnson noise limited operation at frequencies above 100-200 Hz [5]. Some recent data suggest that InAsSbP/InAs/InAsSbP double heterostructure (DH) PDs are superior to SH ones in terms of the zero-bias resistance-area product, R 0• A [6].…”

Low frequency noise in reverse biased double heterostructure P-InAsSbP/n-InAs infrared photodiodes

“…The dashed line in figure 1 is reverse current calculation according to equation (1) using the parameters I 0 = 1.1 × 10 −5 A (I 0 /A = 2.65 × 10 −2 A cm −2 ) and β = 1.20 which have been used to describe forward I-V characteristics of these samples [13]. Note that these values are close to the parameters in single InAs-based heterostructures, β = 1.22 and I 0 /A = 3.4 × 10 −2 A cm −2 [17,18].…”

“…This difference increases up to ∼17 dB at I rb = 3.6 µA. With further increase of current this difference Inset shows similar dependences for SH diodes at the same frequencies f [18]. Adapted from [18].…”

“…The current spectral noise density, S I , was calculated as 2 , where R d is the PD differential resistance. Frequency dependences of the product I × A for DH PD 1211_2 and for SH PD [18] at three values of reverse current I rb (µA): 2, 3.6, and 10 µA. Adapted from [18].…”