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J. Eur. Opt. Society-Rapid Publ. 22, 39( 2026)
Figure
6.( a) Simulated I – V characteristics of the nBn-InGaAs structure and( b) C – V characteristics at 1 kHz.
Figure
7.( a) Reflection and( b) responsivity graphs of the bare and AR-coated surfaces as a function of wavelength.
h 2 ¼ 2pn 2t 2 ð5Þ k See equation( 6) at the bottom of the page.
To facilitate the definition of the reflectance expression in equation( 6), the intermediate relations provided in equations( 1)–( 5) were utilized. Where n 0 is denotes the refractive index of the incident medium, n 1 the refractive index of the Si 3 N 4 layer, n 2 the refractive index of the SiO 2 layer, and n 3 the refractive index of the InP substrate. Similarly, t 1 and t 2 represent the physical thicknesses of the Si 3 N 4 and SiO 2 layers, respectively, while λ corresponds to the wavelength of the incident radiation.
In Figure 7b, the wavelength-dependent responsivity characteristics of the nBn-InGaAs photodetector are presented. To clearly demonstrate the influence of the antireflection coating on photo-response, the responsivity curves of both the AR-coated device and the bare surface are shown together. As observed, the application of the AR layer yields a substantial enhancement in photocarrier
Figure 8. Bias voltage-dependent responsivity graph of nBn- InGaAs structure.
� � r 12 þ r 22 þ r 32 þ r 12 r 22 r 32 þ 2r 1 r 2 1 þ r 32 cos ð 2h1 Þþ2r 2 r 3 1 þ r 12 cos ð 2h2 Þþ2r 1 r 2 r 3 cosð2ðh 1 þ h 2 ÞÞ þ2r
R ¼ 1 r 2 r 3 cosð2ðh 1 � h 2 ÞÞ � �
1 þ r 12 r 22 þ r 22 r 32 þ r 12 r 22 r 32 þ 2r 1 r 2 1 þ r 32 cos ð 2h1 Þþ2r 2 r 3 1 þ r 12 cos ð 2h2 Þþ2r 1 r 2 r 3 cosð2ðh 1 þ h 2 ÞÞ þ2r 1 r 2 r 3 cosð2ðh 1 � h 2 ÞÞ ð6Þ