# INTRODUCTION

oday, the network of data transmission Such as the fitting of Types of the high-speed chip, Internet and telephone communication has created incentives to build and use light detectors. study of the structure of Light metal-semiconductor-metal detectorsfrom the early 1970s began [1]. The surface plasmon resonance in the context of the emergence and realization of sub-wavelength aperture to improve the absorption of light. In recent decades a number of experimental work and theory research to study ultralight transmission through The reviews ultra-light transmission by sub-wavelength aperture is done. [2] Nano grating nano-under-wavelength light creates a robust response and for potential trapping the light in the semiconductor area. Interconnect metalsemiconductor-metal detector electrodes led to a significant increase in bandwidth and reduce the dark current in the detector LED p-i-n structures that have the same active region, is. [3] Detectors plasmonic nanoscale response time due to the distance between the electrodes is about a few tens of picoseconds to the transportation of products from the metal connection is limited. In addition, reducing the distance the electrodes will lead to a reduction in the active region and the decrease in sensitivity. [4] Surface plasmons, which are electromagnetic waves along a metal are released. Properties of their interaction with light, causing surface polariton plasmon waves and create features by which we can photonic components with dimensions much smaller than what has been achieved to build. [5] study and understanding of the plasmons, are widely idea of what began in the 1950s after the article was. These studies also cast a frequent flashpoint of the surface plasmons in thin metal Filter trick of the light scattering of particles of nano metal was done in the early 1970s. Find the improved transmission of light through periodic array of holes with dimensions smaller than the wavelength plasmons in metal films drew much attention. [6] a) The structure design Metal-semiconductor-metal detector structure usually consists of three separate parts, including:

A) metal grating, b) sub-wavelength aperture and f) substrate Is as shown in Figure 1. Part A metal grating that includes a good conductor and the x axis is parallel grooves. Dimensions has been optimized light wavelength surface plasmon polariton is designed to be coupled along the axis x prompt. Surface plasmon polariton wave vector with a period ? for metal grating in Equation 1, we see that in 1991 was used by Soole. In relation (1), ? the angular frequency, ? the angle of the incoming light, c is the speed of light in vacuum and permittivity factor in the metal in the form of equation ( 2) is defined. In reference [1] is mentioned.
? ? = ? ? ? + ?? ?? ? (2)
? ? is the air permittivity used. Each groove surface plasmon polariton ? ??? metal grating by electric field excitation and emission during both positive and negative x-axis location will be done. Surface plasmon polariton wave intensity decreases exponentially with propagation distance and depth is a factor that is proportional to permittivity material. [7] The amplification factor of attraction for "normalized power transition metal grating detector on "normalized power no = structure transition metal grating as in reference [7] are used, we define. The surface plasmon polariton by restrictions on slots (not the center) to release the sub-wavelength aperture triggered a wave of surface plasmon polariton light input (which is presented in Figure ( 1) with ? ? ) interference (coupling) is.] 2] the total surface plasmon polariton increase optical transmission through subwavelength aperture is. In fact, metal grating as collector or lens focused wave in the resonant frequency of the acts. Highly dependent increase in light transmission parameters such as frequency grating ? ? and thick metal grating is ? ð??" . [7] Coupled surface plasmon polariton wave ? ??? of the incoming wave ? ? hybrid transmission ? 12 and it've shown in Figure (2). Using semi-analytical calculation Fabry-Perot [8] and formalism expansion mode [2] Green tensor analysis [9] In reference [7] is calculated; When the subwavelength aperture width x_d is much smaller than the wavelength of emission ? 0 , increase light transmission and improve absorption in semiconductors absorb light transmission caused by metal grating can be achieved. A more accurate model improved light transmission through sub-wavelength aperture as well as by Sturman and et [10] described. Modify the parameters of (1) changes in the semiconductor light transmission is desired wavelength. So we improved the best parameters [7] use.


# b) The simulation desired model

In this article we improve absorption in three stages as follows absorbance at a wavelength of 820 nm have the amplification factor, we speak to all three structures. Finite difference time domain simulation models expressed are using.

We design gold metal grating (Au) and the substrate of gallium arsenide (GaAs) consider. Gold permittivity rate ? ? of Drude-Lorentz model worked in the reference [11] and the coefficient of permittivity substrate (gallium arsenide) ?_sub real value was assumed to be 12.25. The imaginary part for infrared wavelengths were ignored. [12] Fig. 3-A  The idea of putting layers of glass (SiO2) between gold grating and substrate gallium arsenide 1. plasmonic optical detector structure with gold grating and gallium arsenide substrate.

2. plasmonic optical detector structure with gold grating and substrate layers of glass between gold grating and gallium arsenide substrate (under sub-wavelength aperture) of the E-plain Tee is a split in the microwave, is used [13] The detector is also used by Jamalpur et al. was. [14] performance glass substrate which is an insulator for the rejection of electron-hole pairs in the semiconductor to metallic connection. To sum carriers on both sides of the gold structure can be used vertically. In this structure, the absorption rate was 0.24. Figure 4 shows a structure in the form of (4-B) absorption at a wavelength of 820 nm curve we see. Our silver nanoparticles under sub-wavelength aperture (in place of glass layer) placed. This is similar to gallium arsenide substrate and intermediate layer of germanium. [15] Due to the high refractive index semiconductor base frequency must be chosen too small metallic nanoparticles. It features some difficult and sensitive process with a common manufacturing techniques. In this structure, the absorption rate was 0.31. Figure 5 shows a structure in the form of (5-b) absorption at a wavelength of 820 nm curve we see.  In this paper, results of the three proposed structure your previous jobs on the graph (1) We compare the amplification factor of attraction for "normalized power transition detector with metal grating" on "normalized power without transition metal grating " in [7] is used to optimize and use our sub-contractor relations.
??? = ? ???,ð??" ? ??? (3)
Explaining the relation ( 3) is as follows: Absorption Enhancement Factor as the ratio of: the normalized power transmittance of the metal-grating MSM photo detector to the normalized power transmittance of an MSM photo detector structure without a metal grating.

This relationship is expressed for the results of three structures and substrate in the denominator we can use as a reference gallium arsenide. Normalized power transmission substrate gallium arsenide (without metal grating) in the form ( 6) is shown at a wavelength of 820 nm is equal to 0.012. we have established that by performing finite element EM computation to the following expression, the absorption QE, labeled as ?, of any detector geometry can be predicted [16]:
? = ?? ?? 0 2 ? |? ? (? ?)| 2 ? 3 ? ? (4)
where n is the material refractive index of the detector material, ? is the absorption coefficient for vertically polarized light, A is the detector area, E0 is the incident electric field from the air, V is the detector active volume, Ez is the self-consistent vertical electric field. Equation ( 4) states that QE can be calculated from the volume integral of |Ez |2 in the presence of a finite ?. Since E0 and Ez are linearly proportional to each other, E0 can be set arbitrarily, and the only input parameter in (1) is the wavelength-dependent ?(?), which can be calculated based on the material layer structure [17]. For a known ?(?), there will be no more free parameters, and the value of ?(?) is uniquely and unambiguously determined. To solve Ez numerically, we use a commercial finite element solver. In addition to ?, we also define another quantity, the external QE or ?ext , which is QE × pixel area fill factor (?A/Apitch). (5)

Which represents an increase absorption due to grating adjusting parameters compared with similar structure. Results of the 2-3 structure plasmonic optical detector with gallium arsenide layers of glass between Gold grating and substrate in equation ( 2), we have:
??? = 0.243 0.012 = 20.25(6)
Results 3-3 of plasmonic optical detector structure with silver nanoparticles on glass substrates, gallium arsenide between Gold grating and infrastructure in equation ( 2) we have:
??? = 0.31 0.012 = 25.83(7)
II.


# Simulation Setup

The 3D -plasmonic optical detector structure shown in Fig. 5(a) was simulated using the FDTD software package developed by Lumerical. For the FDTD simulation, we used a mesh size 10nm. This highresolution sampling yielded convergent solutions at reasonable computation times. A periodic boundary condition was assumed along the y-direction for an incident light wave propagated along the normal direction. perfectly matched layer (PML) boundary III.


# Conclusion

In this article we construct the optical detection based on plasmonic effects by improving the detection parameters for maximum light absorption at a wavelength of 820 nm have suggested. We improved amplification factor of attraction even for the initial state, including gold and base gallium arsenide grating was obtained as a result of adjusting parameters grating compared with a similar structure and was 14 times. The coefficient of resonant absorption by adding layers of glass between gold grating and base the amount of gallium arsenide 20.25 for the glass came up with. Then proceeded to put silver nanoparticles on glass substrates that absorb amplification factor increased to 25.83. Compared with previous work Jamalpur and colleagues [14] in 2015 which attracted about 15 have reached the amplification factor, we have increased every neighborhood we have our final difference is the structure of 10.83.
1![Fig. 1: Structure of the metal detector with diffraction, sub-wavelength aperture and substrate provided by tan and et](image-2.png "Fig. 1 :")
![XVII Issue I Version I](image-3.png "")
2![Fig. 2: Modified model of attract high above based the Fabry-Perot model-based presented in reference [8] red zone (where ? 23 located) has a high energy intensity and energy intensity is less water locations](image-4.png "Fig. 2 :")
![Fig. 3-A: proposed framework for gold grating and gallium arsenide substrate detector In this model, the (3-a) by setting the parameter can be reached absorb light in the desired wavelength, the absorption rate for the model in Figure (3-b) shown is equal to 0.16.](image-5.png "")
3![Fig. 3-b: the normalized power absorbance detector with gold grating and gallium arsenide substrate](image-6.png "Fig. 3 -")
4![Fig. 4 -A: our proposal model for detector with substrate layers of glass between gold grating and gallium arsenide substrate](image-7.png "Fig. 4 -")
5![Fig. 5-A: Our proposed model for plasmonic optical detector with silver nanoparticles on glass layer, between gold grating and gallium arsenide substrate](image-8.png "Fig. 5 -")
5![Fig. 5 (b): normalized power absorption optical detector plasmonic with silver nanoparticles on glass layer, between gold grating and gallium arsenide substrate c) Data of modelsIn this paper, results of the three proposed structure your previous jobs on the graph (1) We compare the amplification factor of attraction for "normalized power transition detector with metal grating" on "normalized power without transition metal grating " in[7] is used to optimize and use our sub-contractor relations.](image-9.png "Fig. 5 (")
6![Fig. 6: normalized power transmission gallium arsenide substrate (without metal grating)](image-10.png "Fig. 6 :")
7![Fig. 7-a: Plot of EM spectroscopy in linear type](image-11.png "Fig. 7 -")
![Absorption Improvement and EM Spectroscopy in Photodetector byIntroducing Sio2 Layer and Ag Nano Particles4. EM Modelcondition was assumed along the y-direction to accurately simulate the absorption of the light reflected from the bottom as well as light transmitted from the top boundaries of the simulated plasmonic optical detector structure.](image-12.png "F")
			Year 2017 F © 2017 Global Journals Inc. (US)
			© 2017 Global Journals Inc. (US)
			. plasmonic optical detector structure with silver nanoparticles on glass substrates, between gold grating and gallium arsenide substrate
		
		
			

				


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