Te Avalanche Photodiodes Research Articles

Monte Carlo simulations of Hg0.7Cd0.3Te avalanche photodiodes and resonance phenomenon in the multiplication noise

Monte Carlo simulations of Hg0.7Cd0.3Te avalanche photodiodes are presented. The simulated very low excess noise and exponential gain curve are consistent with those that have been experimentally observed and are consistent with the speculated large ratio of electron and hole impact ionization rates. The simulations suggest that there is a large difference between the scattering rates of electrons and holes, a direct consequence of the band structure. A resonance behavior in the excess noise factor at gain values near 2, 4, 8, and 16 is also revealed in the simulations. This effect is explained by comparing to the gain and noise of a photomultiplier tube.

Anomalous multiplication in Hg0.56Cd0.44Te avalanche photodiodes

We quantitatively study the electric field distributions in Hg0.56Cd0.44Te avalanche photodiodes recently reported for use in the 1.6–2.5 μm wavelength region using a two-dimensional solution of Poisson’s equation. It is found that, contrary to previous reports, there is no evidence for large uniform avalanche gain in these diodes. Furthermore, to first order, it is shown that the ionization rate ratio of electrons to holes in the diodes demonstrated to date is on the order of unity. Hence, it is not expected that the present diodes will lead to low noise operation superior to Ge or In0.53Ga0.47As/InP avalanche photodetectors.

Impact ionization resonance and auger recombination in Hg<inf>1 - x</inf>Cd<inf>x</inf>Te (<tex>0.6 ≤ x ≤ 0.7</tex>)

The purpose of this paper is the study of the impact ionization and the Auger recombination in Hg 1-x Cd x Te avalanche photodiodes, with 0.6 \leq x \leq 0.7 . For x \sim 0.7 it is shown that the spin orbit splitting Δ is lower than the bandgap energy E g so that impact ionization is initiated by holes from the Split-off valence band. For x \sim 0.6, \Delta \sim E_{g} , the rate of the Auger recombination is maximum, corresponding to a resonant impact ionization and to a maximum ratio k = \beta / \alpha where α and β are, respectively, the impact ionization coefficient for electrons and holes.

Les photodiodes à avalanche Hg0,4Cd0,6Te à λ = 1,55 μm. Bruit près de la résonance due au couplage spin-orbite

This contribution is devoted to the electrical and optical characterization of three Hg 1−x Cd x Te avalanche photodiodes from planar technology with composition parameter x near 0.6. This alloy composition leads to devices that are well suited for 1.55 μm detection. From the noise analysis under multiplication we intend to show the tight dependence of the ratio K=β/a ― of the hole and electron ionization coefficients respectively ― upon the ratio Δ/E g or x. It so turns out that in these Hg 1−x Cd x Te alloys around x=60%, Δ is very close to E g therefore k reaches its maximum value. Due to this physical property, this II-VI alloy may be considered as a good candidate among the semiconductor materials from which 1.3 to 1.6 μm avalanche photodiodes could be made and used in the fibre optics transmission systems [1,2] On presente une caracterisation electrique et optique d'un essai de photodetecteurs a avalanche pour de futures applications aux reseaux câbles par fibres optiques dans la fenetre λ=1,55 μm

An Hg0.3Cd0.7Te avalanche photodiode for optical-fiber transmission systems at λ = 1.3 µm

The purpose of this paper is the characterization of Hg <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.3</inf> Cd <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.7</inf> Te avalanche photodiodes at γ = 1.3 µm. These devices are manufactured by tile Société Anonyme des Télécommunications. The multiplication noise for these APD's is measured. The value of the ratio <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">k</tex> = β/α is deduced from noise measurements, β and α being, respectively, the hole and electron ionization coefficients. It is shown that these HgCdTe APD's are promising candidates for detectors of 1.3-µm optical communication.

Impact ionization rates for electrons and holes in Hg 0.3Cd 0.7Te in avalanche photodiodes for optical fiber transmission systems at λ = 1.3 μm

In this paper preliminary experimental results are shown on Hg 0.3Cd 0.7Te avalanche photodiodes with x = 0.70 and E g = 0.84 eV. In the first part, both multiplication coefficients M p and M n,p are determined. The ionization coefficients α and β for electrons and holes are calculated. The ionization coefficient ratio, k = β/α, is deduced and is about 10. In the second part, noise characterization will be presented. The excess noise F( M), given by McIntyre's theory, confirms that k is about 10.