Gradually Thermal Diffusing of Silver on Amorphous GeSe Thin Film; Structural and Optical Properties

doi:10.21203/rs.3.rs-5005888/v1

Binary glasses of GeSe are prepared by melt quench technique. Two layers of thin film preparation have been done by the conventional thermal evaporation technique on glass substrate. GeSe with 340 ± 5 nm thickness is prepared as first layer, then thin silver layer are evaporated on top of the GeSe film. The GeSe with Ag on top of the film were annealed at different time of 30, 60, 90, and 180 and 210 min at 573 K of temperature. Subsequently, we have analyzed the films using scanning electron microscopy (SEM) and X-ray diffraction (XRD) to confirm the successful diffusion of Ag on GeSe films. XRD measurements show that as prepared Ag/GeSe have amorphous natures. Optical transmission and reflection spectra of the studied thin films are measured in the wavelength range of 200 − 2500 nm at room temperature. The optical properties of the new films were studied before and after annealing at different annealing times due to gradually thermal diffusing of Silver on GaAs. The absorption coefficient (α) as an optical constant is determined as a function of annealing times. Moreover, the values of the third-order nonlinear optical susceptibility increased with an increase of annealing temperatures due to gradually thermal diffusing of Silver. The results indicate that Ag/GeSe has great potential for various applications including optical sensors and optoelectronics.

Ag

GeSe

Thin films

structural investigations

Thermal effect

Optical constants

Chalcogenide GaAs is a type of amorphous semiconductor that contains germanium, arsenic, and one or more of the chalcogen elements (sulfur, selenium, or tellurium). Chalcogenide GaAs has unique optical, electrical, and thermal properties that make it suitable for various applications, such as phase-change memory, nanomedicine, and optoelectronics [1]. GaAs films can be deposited on crystalline GaAs substrates to form heterojunctions, which are junctions between two different types of semiconductors. These heterojunctions can exhibit negative differential resistance, low forward resistance, and strong current saturation, depending on the bias voltage and the state of the chalcogenide glass [2]. These films can provide a low-loss, thermally stable, and mechanically robust bonding layer for GaAs OPO elements [3]. Silver (Ag) is a metal that can diffuse into gallium arsenide (GaAs), a compound semiconductor, and form ohmic contacts or Schottky barriers, depending on the doping type and concentration of GaAs. Ag diffusion into GaAs can be achieved by various methods, such as thermal annealing, ion implantation, or laser irradiation [4]. The diffusion mechanism and depth of Ag in GaAs depend on the temperature, time, and energy of the diffusion process, as well as the initial thickness and morphology of the Ag layer [5]. This diffusion can alter the electrical, optical, and structural properties of GaAs, such as the carrier concentration, band gap, lattice constant, and defect density. It also affect the performance and reliability of GaAs-based devices, such as solar cells, light-emitting diodes, lasers, and transistors. Therefore, it is an important phenomenon to study and control for the fabrication and optimization of GaAs devices. The post-growth treatments, such as annealing, ion implantation, or laser irradiation, can also modify the structural properties of GaAs films, such as the defect density, the lattice parameter, the grain size, and the crystallinity. For example, annealing can enhance the diffusion and the recrystallization of GaAs films, reducing the defects and improving the electrical properties. Ion implantation can introduce dopants or defects into GaAs films, changing their conductivity and optical properties. The growth parameters of GaAs, such as the temperature, pressure, flux ratio, and doping, can affect the crystalline quality, the morphology, the composition, and the strain of the films[6][7].

In this study, melt quench is a tool which used to prepare GeSe binary glasses. The thermal evaporation method has been used to prepare two layers of thin films on a glass substrate. A first layer of GeSe with a thickness of 340 ± 5 nm is prepared, and on top of it, a very thin layer of evaporated silver is applied. Different temperatures of 30, 60, 90, 180, and 210 minutes at 573 K were used to anneal the GeSe with Ag on top of the film. Various structural investigations have been done using SEM and XRD. The effect of varying the annealing time on the optical properties of Ag on top of GaAs films has been done. We believe that the findings from our research could be beneficial for several implications for various fields, including material science, optoelectronics, and the development of new functional materials and devices.

The bulk material for GeAs glasses was created using the well-known melt quenching technique using 4N pure Ge and As. A highly sensitive digital balance with an accuracy of 0.01 mg was used to measure the required amounts of the components. After the materials were measured, they were placed in a clean, cleared, fixed silica tube and heated to a constant temperature of 1273 K using a temperature controller for a full day. To ensure composite homogeneity, the tube was shaken at regular intervals during the heating process. After that, an ice bath was used to quench the tube.

GeAs films were produced by a thermal evaporation process with a coating unit (HHV Auto 306). The films were applied to previously clean optically glass substrates. To get uniformly fabricated films at a distance of 25 cm above the evaporator, the substrate was placed onto a rotatable holder. The substrates were maintained at room temperature while the GeAs films were being created in a vacuum stronger than 10^− 4 Pa. The film thickness of 340 ± 5 nm was achieved by controlling the deposition rate at 4.2 nm/s using the quartz crystal thickness monitor, and verifying the film thickness using the interferometric technique. The Ag/Ge₂₅Se₇₅ films were annealed at 573 K at different times of 30, 60, 90, 180 and 210 min. in the vacuum. X-ray diffraction (XRD) was used to examine the structural characteristics of the as-prepared films using a Philips diffractometer 1710 with a Ni-sifted CuKα source (λ = 0.15418 nm). The structure details of the films are investigated using the scanning electron microscope (SEM). Using a double-beam spectrophotometer (JASCO, V-570 UV VIS NIR), the transmittance, T, and reflectance, R, of the films were measured in the wavelength (λ) range of 200–2500 nm.

3.1 Structural investigations

As well known that, amorphous materials are difficult to characterize as a broad hump using XRD, which don’t produce sharp diffraction peaks. Therefore, Fig. 1 shows XRD of as prepared and annealed Ag/Ge₂₅Se₇₅ films at 573 K at different annealing times of 30, 60, 90 and 210 min. For as prepared Ag/Ge₂₅Se₇₅ films, it shows an amorphous nature without distinguish peaks. On the other hand after annealed at 573 K for 30 min., still amorphous nature with distinguish peak of GeSe₂ at 72.19^o. At increasing annealing times of 60, 90 and 210 min, six distinguish peak of GeSe₂ were appeared at 14.4^o, 29.25^o, 41.56^o, 44.72^o, 61.14^o and 72.19^o. All distinguish peak were comprised with JCPDS file No. as illustrate in Table 1. At annealed of 573 K at 210 min. there are two peaks of silver were appeared at 79 and 82^o which are shifted to a higher values compared to the original card Ref. No. (0.1-0.87-0.719) due to many reasons such as lattice parameters, Microstructure parameter or thermal annealing which considered as the main reason of the present case. Furthermore, the average crystalline size of the thin films, D, is usually obtained[8] $\:D=\frac{0.94\lambda\:}{\beta\:cos\theta\:}$ where λ is X-ray wavelength, β is the full width at half maximum (FWHM) in radiant and θ is the Bragg’s angle. Indeed the strain value, ε, is determined by the following relation[9][10] $\:\epsilon\:=\frac{\beta\:}{4tan\theta\:}$ whereas the dislocation density,$\:\delta\:$, was calculated according to the following equation[11] $\:\delta\:=\frac{1}{{D}^{2}}$. The calculated value of crystallite size, D, the dislocation density, $\:\delta\:$, and the lattice strain, ε, were listed in Table 1. This table shows that the values of D increase with the increasing of annealing time. This result can be explained due to the decline of lattice defects along the grain boundaries as Ag diffusion increased inside the GaAs films[12], whilst the values of $\:\delta\:$ and ε decrease with the increasing of annealing temperature.

Table 1

Structural parameters Crystalline calculated of as prepared and annealed (Ge₂₅Se₇₅)Ag films at 573 K at different times of 30, 60, 90 and 210 min.
Annealing time (min.)	Kind of Phase	h k l	d._exp.	d. _stand	Average of crystallite size for GeSe phase (D) (nm)	Strain values (ɛ) × 10^− 3 (lin^− 2.m^− 4)	dislocation density δ × 10¹⁴ (lines/m²)	JCPDS file No.
0	GeSe₂	315	1.308	1.30821	18.55	1.95	3.655	04-003-4149
30	GeSe₂	315	1.308	1.30821	15.88	2.28	4.99	04-003-4149
60	GeSe₂	026	1.31	1.30821	20.24 18.37	1.79 1.97	3.0714 3.7285	04-003-4149 85–0566
60	Se	012	2.034	2.0318	20.24 18.37	1.79 1.97	3.0714 3.7285	04-003-4149 85–0566
90	GeSe₂ GeSe₂ GeSe₂	110 105 315	6.088 3.038 1.309	6.07 3.0400 1.30821	21.595 20.8	1.72 1.74	2.93 2.9082	16–0080 33–0581 04-003-4149 85–0566
90	Se	012	2.034	2.0318	21.595 20.8	1.72 1.74	2.93 2.9082	16–0080 33–0581 04-003-4149 85–0566
210	GeSe₂ GeSe₂ GeSe₂	020 105 315	6.174 3.052 1.309	6.15 3.0400 1.30821	23.78 32.8	1.76 1.135	3.26 1.27	16–0080 33–0581 04-003-4149 73-2087 85–0566 83-2438
	Se	520	2.165	2.1653
	Se	314	2.026	2.025
	Se	103	1.516	1.5153

SEM images of as prepared and annealed Ag/Ge₂₅Se₇₅ films at 573 K at different annealing times of 30, 90 and 210 min are shown Fig. 2. The surface monographic of the as prepared films is recognized by its uniformly spherical shape. As the annealing temperature increases, the size of these small white spots increase with increasing annealed times. These spots related to gradually thermal diffusing of silver on amorphous GeSe thin film which confirm the XRD results. The average size of these spherical particles is found to be about 500 nm, whilst the diameter of the spherical particles for annealed films at 573 K at different annealing times of 30, 60, 90 and 210 min are ranging from 500 nm to 2000 nm. This phenomenon could be expounded due to the effect of the annealing time in removing the defects, and therefore the accumulation of particles is proposed to be occurred[13]. Moreover, Image J program was using for analyzing the images which shown in Fig. 3. These analyses confirm the increasing of particles agglomeration with annealing time from 350, 550 and 700 nm due to gradually thermal diffusing of Silver.

3.2 Linear optical investigations

3.2.1 Absorption parameters

Linear optical analysis aimed to assess various optical parameters and constants and forecast their possible uses. The transmittance of a medium or a material is the fraction of light that passes through the other side of the medium or the proportion of the light energy hitting it to the light going through it. The estimated values of transmittance (T) and reflectance (R) provide a simpler method for calculating important optical parameters such as optical bandgap, localized state refractive index width, and other parameters. As the light travels through any medium, it can be transmitted, reflected, or absorbed. T and R characteristics of Ag/Ge₂₅Se₇₅ films were examined in relation to incident wavelength (λ). Figure 4 displays both T and R at different λ values from ultraviolet to near-infrared (200–2500 nm) for Ag/Ge₂₅Se₇₅ films at 573 K at different annealing times of 30, 60, 90, 180 and 210 min. it can be seen form that figure, in the ultraviolet region (200–500 nm), T values rose considerably with λ. However, as the λ increased more, the rate of rise in T became smaller, eventually stabilizing for the remaining λ range. The Ag/Ge₂₅Se₇₅ films at 573 K at different annealing times of 30, 60, 90, 180 and 210 min showed high transmittance values for wavelengths (500 ≤ λ ≤ 800 nm). As the annealing time went up from 30 to 210 min, the measured transmittance value also went up. In contrast, the R values of the prepared samples displayed a different pattern than T. The R values were lower throughout the examined λ range, with an average value around 4%. The annealing time shows a nonlinear variation when T or R is changed.

Ag/Ge₂₅Se₇₅ films can be used in applications that require transparent materials, such as packaging material for optoelectronic and microelectronic devices. Therefore, the estimated value of absorption coefficient (α) was calculated using[14]:

$$\:\alpha\:=\frac{1}{d}ln\left[\frac{(1-{R}^{2})}{2T}+\sqrt{{R}^{2}+\frac{(1-{R}^{2})}{4{T}^{2}}}\right]$$

1

d: thickness, T: transmittance and R: reflectance.

The absorption coefficient (α) is a measure of how well a substance can absorb light with a specific wavelength per unit length. It provides information about each absorber molecule or ion and the nature of the electronic transition. The absorption coefficient determines whether the electronic transition will occur directly or indirectly. Changes in the absorption coefficient can be attributed to annealing times of 30, 60, 90, 180 and 210 min. As shown in Fig. 5, the value of α increases as the photon energy increases, while in the range of (0.5-2.0 eV), a shoulder is observed. As the annealing time increases, the value of α decreases. Therefore, more Ag diffuse in layer of GaAs films, which enhance the absorption of the present films. Figures 6 and 7 show the plot of (αhν)^1/2 and (αhν)² against the photon energy (hν) for Ag/Ge₂₅Se₇₅ films at 573 K and different annealing times of 30, 60, 90, 180 and 210 min.

The first two plots are driven using[15] :

$$\:{\left(\alpha\:h\upsilon\:\right)}^{r}=const.(h\upsilon\:-{E}_{g})$$

2

The plots of (αhν)^1/2 and (αhν)² show linear relationships with photon energy at higher energy levels, indicating that Ag/Ge₂₅Se₇₅ films at 573 K and different annealing times of 30, 60, 90, 180 and 210 min exhibit indirect optical transitions. The more fitting relation indicate that indirect transition is the majority one in these samples due to Ag in Ge₂₅Se₇₅ which create localized states in Ge₂₅Se₇₅ samples. The intercepts of the lines yield estimated values for the direct and indirect optical bandgap (E_g) for the respective samples as listed in Table 1. It is well known that the E_g of a material can be affected by various factors, such as temperature, pressure, doping, and grain size, therefore it is changed due to gradually thermal diffusing of silver.

The amount of light that a material absorbs at a specific wavelength is measured by its extinction coefficient. The mass extinction coefficient, molar extinction coefficient, optical extinction coefficient, and other units can be used to express it. The size, shape, composition, and structure of the material are among the physical and chemical characteristics that affect the extinction coefficient. The extension coefficient (k_ex), using an equation[16]

$$\:{k}_{ex}=\frac{\alpha\:\lambda\:}{4\pi\:}$$

3

Figure 8 depict the extension coefficient (k_ex) versus photon energy (eV) for Ag/Ge₂₅Se₇₅ films at 573 K and different annealing times of 30, 60, 90, 180 and 210 min.

3.2.2 Dispersion parameters

The refractive index (n) versus the wavelength (λ) is illustrated in Fig. 7 for Ag/Ge₂₅Se₇₅ films at 573 K and different annealing times of 30, 60, 90, 180 and 210 min, respectively was estimated from[17]

$$\:n=\sqrt{\frac{4R}{{(R-1)}^{2}}-{k}_{ex}^{2}}+\frac{R+1}{R-1}$$

4

Both k_ex and n follow a similar trend to α. In the ultraviolet (UV) region, at wavelengths shorter than 275 nm (≤ 4.5 eV), their values abruptly drop from higher values before progressively increasing with additional wavelength. For Ag/Ge₂₅Se₇₅ films, k_ex values vary from 0 to 1 and get smaller as the annealing time increases. At 1000 nm, the refractive index reaches its maximum value of 6, with an average range of 2 to 6 [18].

Figures 9 and 10 illustrates the real part of the dielectric constant (ε_r) and the imaginary part of the dielectric constant (ε_i), respectively, as a function of the wavelength (λ) for Ag/Ge₂₅Se₇₅ films at 573 K and various annealing times of 30, 60, 90, 180 and 210 min.

The values of (ε_r) and (ε_i) were derived from the equation [19].

$$\:{\epsilon\:}_{r}={n}^{2}-{k}_{ex}^{2}$$

5

$$\:{\epsilon\:}_{i}=2n{k}_{ex}$$

6

An increase in the annealing times causes minor changes in the dielectric constants of (Ge₂₅Se₇₅)Ag, specifically the real part (ε_r) and the imaginary part (ε_i). For the same wavelength, ε_i is smaller than ε_r. When wavelengths surpass 450 nm, there is a slight increase in ε_i and a decrease in ε_r. While ε_i reaches a stable value, ε_r reaches its maximum value at 1200 nm[19]. A portion of the optical energy is lost when it drops below the optical bandgap. Dispersion parameters, such as the static refractive index, dispersion energy, and single oscillator energy, can be used to quantify this lost energy. The Wemple-DiDomenico model is used to compute these parameters[20].

Figure 11 displays a graph of (n²-1)⁻¹ versus (hυ)² for Ag/Ge₂₅Se₇₅ films at 573 K and various annealing times of 30, 60, 90, 180 and 210 min.

The experimental data was fitted to straight lines using a specific formula[21]

$$\:{({n}^{2}-1)}^{-1}=\frac{{E}_{a}}{{E}_{d}}-\frac{{\left(h\upsilon\:\right)}^{2}}{{E}_{o}{E}_{d}}$$

7

$$\:{\epsilon\:}_{\infty\:}={n}_{o}^{2}=1+\frac{{E}_{d}}{{E}_{a}}$$

8

Based on the slope and intercept of the straight lines, Table 2 presents the estimated values of the oscillator's average energy (E_a) and the inter-band optical transitions' average strength (E_d).

Table 2

Deduced optical parameters of as prepared and annealed Ag/Ge₂₅Se₇₅ films at 573 K at different times of 30, 60, 90 and 210 min.
Annealing time (min.)	Eⁱⁿ_g	E^di_g	E_a	E_d	$\:{n}_{\infty\:}^{2}$	$\:{n}_{\infty\:}$	M_− 1	M_− 3	$\:{n}_{o}$	$\:{\epsilon\:}_{L}$	$\:\frac{N}{{m}^{*}}$x10⁵⁰
0	2.02	3.23	1.16	4.31	4.72	2.17	3.72	2.76254	3.33467	11.12	10.08
30	1.99	2.70	1.17	3.09	3.63	1.91	2.63	1.91	2.79	7.76	6.66
60	2.26	3.16	1.13	4.81	5.26	2.29	4.26	3.34	3.59	12.86	11.97
90	2.30	3.13	1.14	5.41	5.74	2.40	4.74	3.64	3.77	14.22	13.93
180	2.16	3.21	1.07	5.08	5.74	2.40	4.74	4.13	4.14	17.10	19.76
210	2.06	3.10	1.14	4.89	5.31	2.30	4.31	3.34	3.60	12.99	12.44

Table 2 revealed that ε ∞ and no were both dependent on annealing times of 30, 60, 90, 180 and 210 min. In addition, WDD [22]states that two additional optical dispersion parameters that describe the strength of the inter-band transition are the optical spectrum moments, M_− 1 and M_− 3. The following equations relate these parameters to the optical dispersion parameters E_o and E_d[23]:

$$\:{M}_{-1}=\frac{{E}_{d}}{{E}_{o}},\:{M}_{-3}=\frac{{M}_{-1}}{{E}_{o}^{2}}$$

9

The computed values for M-1 and M-3 are listed in Table 2. As the annealing times increased, the values of M_− 1 and M_− 3 increased. When the annealing times rises, the trends of E_d and E_a shift in the same directions[24]. The formula based on the E_o and E_d parameters can be used to determine the static refractive index[24]:

$$\:{n}_{o}=\sqrt{1+\frac{{E}_{d}}{{E}_{a}}}$$

10

The Ag/Ge₂₅Se₇₅ films ratio's value of n_o. In addition, the high-frequency dielectric constant and the ratio of charge carrier concentration (N) to the effective mass of the electron (m*) were determined using Sellmeier's model. The plot for Ag/Ge₂₅Se₇₅ films in Fig. 12 shows the relationship between n² and λ². Interestingly, the experimental data shows an amazing agreement with straight lines according to the previously mentioned equation[25].

The relationship between a transparent material's refractive index and light wavelength is represented by Sellmeier's model. Light bending as it enters or leaves a material is measured by the refractive index. An equation involving some experimentally determined coefficients is used in Sellmeier's model. If the material doesn't absorb light in that range, the formula can be used to determine the refractive index for any wavelength.

We can also learn more about how light disperses, or splits into different colors, when it passes through materials using Sellmeier's model. As the annealing time increases, the value of no for Ag/Ge₂₅Se₇₅ films decreases. In addition, the high-frequency dielectric constant and the ratio of charge carrier concentration (N) to the effective mass of the electron (m*) were determined using Sellmeier's model. The plot for Ag/Ge₂₅Se₇₅ films in Fig. 13 shows the relationship between n² and λ². The experimental data shows an agreement with straight lines according to the previously mentioned equation[14].

$$\:{n}^{2}={\epsilon\:}_{\infty\:}-\frac{{e}^{2}}{4{\pi\:}^{2}{\epsilon\:}_{o}{c}^{2}}\frac{N}{{m}^{*}}{\lambda\:}^{2}$$

11

The symbols for the high-frequency dielectric constant, vacuum permittivity, and speed of light in this equation are$\:{\:\epsilon\:}_{\infty\:}$, $\:{\epsilon\:}_{o}$, and c, respectively. In the composite, the free carrier concentration drops to 1.37 x10⁵⁰ when the annealing time is raised. The estimated values of $\:{\epsilon\:}_{\infty\:}$ and$\:\:\frac{N}{{m}^{*}}$, are listed in Table 2, and the formula of $\:{\epsilon\:}_{\infty\:\:}={n}_{o}^{2}\:$ is confirmed by the estimated values of n_o and $\:{\epsilon\:}_{\infty\:\:}$.

3.3 Nonlinear optical investigations

The area of optics known as nonlinear optical studies the behavior of light in materials that respond to light's electric field in a nonlinear way. This indicates that the intensity and form of the light wave affect the material's polarization, which is a measurement of the alignment of the electric charges. Optical switching, self-focusing, frequency conversion, and optical solutions are examples of phenomena that can be produced by nonlinear optical effects. A broad range of optical applications can be made more expansible by having an understanding of the third order type of nonlinear optical susceptibility, χ(3) [26]. When a material is exposed to a strong electric field, like a laser beam, its polarization changes. This phenomenon is known as third-order nonlinear optical susceptibility. The measurement of a material's electric charge alignment is called polarization. Self-focusing, optical switching, and frequency conversion are examples of effects that can result from third-order nonlinear optical susceptibility. The material's composition and structure determine the value of third-order nonlinear optical susceptibility. The kind and concentration of atoms or molecules, the existence of flaws or contaminants, the temperature, and the light's wavelength are a few variables that may have an impact. Depending on how the material's constituents interact with the polarization and electric field, adding or removing certain elements can change the third-order nonlinear optical susceptibility. Using Miller's principle, χ(3) can be computed using [27].

$\:{\chi\:}^{\left(3\right)}=\frac{A{\left({n}_{o}^{2}-1\right)}^{4}}{{\left(4\pi\:\right)}^{4}}$, A = 1.7×10⁻¹⁰ esu.

(12)

This equation is used to calculate the nonlinear refractive index, or n₂, by combining the Miller principle with a single effective oscillator.[27]

Table 3 lists the values of χ(3) and n₂ for (Ge₂₅Se₇₅)Ag films. It is evident that the computed χ(3) values decrease as the annealing time content increases. A few variables that may impact the annealing time third-order nonlinear optical susceptibility are the kind and quantity of metal ions present, the solvent's concentration and polarity, temperature, and light wavelength. Clearly, all these parameters were affected by diffusing of Ag on the GaAs films. Therefore, the change of the third order type of nonlinear optical susceptibility and the nonlinear refractive index due to gradually thermal diffusing of Ag on amorphous GeSe thin film.

$\:{n}_{2}=\frac{12\pi\:}{{n}_{o}}{\chi\:}^{\left(3\right)}$

(13)

XRD and SEM confirmed the amorphous nature of Ag/Ge₂₅Se₇₅films. SEM analysis showed Ag/Ge₂₅Se₇₅films that increasing of particles agglomeration with annealing time from 350, 550 and 700 nm indicated to formation of Ag on the surface of Ge₂₅Se₇₅ films. Optical investigations showed that annealing time change of optical band gap, oscillator's average energy and the inter-band optical transitions' average strength. A few variables impact the annealing time third-order nonlinear optical susceptibility is quantity of metal ions present due to annealing time. The third order type of nonlinear optical susceptibility (2.058-3.71) and the nonlinear refractive index (3.57-6.08) due to gradually thermal diffusing of silver on amorphous GeSe thin film. Our study's findings show that Ag/Ge₂₅Se₇₅films has a lot of potential applications, such as optoelectronics and optics.

The authors confirm that there are no conflict of Interest.

Acknowledgments

The authors extend their appreciation to the Deputyship for Research & Innovation, Ministry of Education in Saudi Arabia for funding this research work through the project number 445-9-797.

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No competing interests reported.

Gradually Thermal Diffusing of Silver on Amorphous GeSe Thin Film; Structural and Optical Properties

Status:

Journal Publication

Version 1

Abstract

Figures

1. Introduction

2. Experimental techniques

3. Results and discussion

3.1 Structural investigations

3.2 Linear optical investigations

3.2.1 Absorption parameters

3.2.2 Dispersion parameters

3.3 Nonlinear optical investigations

Conclusion

Declarations

References

Additional Declarations

Status:

Journal Publication

Version 1