Skip to main content
NCBI home page
ACS Omega logoLink to ACS Omega
. 2024 May 2;9(19):21346–21352. doi: 10.1021/acsomega.4c01585

Electrical Properties of Laser Patterned Schottky Diode with ALD-Grown TiO2 Interlayer

Elanur Dikicioǧlu 1,*, M Burcu Balı 2, Semran Saǧlam 2, Halil Berberoǧlu 3, Ihor Pavlov 4,5, Arian Goodarzi 5, Elif Orhan 2,*
PMCID: PMC11097149  PMID: 38764680

Abstract

graphic file with name ao4c01585_0006.jpg

Heterojunction formation is the key to adjusting the electronic and optoelectronic properties of various semiconductor devices. There have been various reports on the formation and importance of semiconducting heterojunction devices based on metal oxides. Titanium dioxide (TiO2) is one of the metal oxides that has many unique properties. TiO2’s importance is due to its physical and chemical properties such as large band gap, large permittivity, stability, and low leakage current density. In this context, we present the electrical properties of the metal–insulator–semiconductor (MIS) type-TiO2-based Schottky barrier diode (SBD) in the study. To create a thin layer of TiO2 on p-type silicon (p-type Si) patterned partially by the laser-induced periodic surface structure (LIPSS) technique, an atomic layer deposition (ALD) technique was used in the study. For comparison, the current–voltage (I–V) characteristics of the TiO2-based laser-patterned (LP) and nonlaser-patterned (non-LP) diodes were measured at 300 K and in the dark at ±5 V. Classical thermionic emission (TE) theory and Cheung functions were used to investigate the critical diode parameters of the diodes, including ideality factor (n), series resistance (Rs), and barrier height (Φb). The n values were obtained as 4.10 and 3.68 from the TE method and Cheung functions for the LP diode, respectively. The Φb values were found as 0.68 and 0.69 eV from the TE method and Cheung functions, respectively. According to experimental results, the laser patterning resulted in an increase in the Φb values and a decrease in the n values. After laser patterning, it was observed that the device worked effectively, and the ideality factor and barrier height values were improved. This study provides insight into the fabrication and electrical properties of TiO2-based heterojunction devices.

1. Introduction

A semiconductor device called a Schottky diode is created when a metal and a semiconductor come together. This diode generates an energy barrier using a metal–semiconductor junction. Schottky diodes are dependent on the energy barrier that develops at the interface between a semiconductor and a metal. Because of their quick switching speed and limited reverse voltage tolerance, diodes are frequently used in high-frequency applications. They also display nonlinear voltage–current characteristics. Metals, insulators, and semiconductors are all combined to form metal–insulator–semiconductor (MIS) structures. By adjusting the electric field, this arrangement may regulate the carrier density on the semiconductor surface. MIS structures are frequently seen as components with a capacitance. The semiconductor surface is connected to the insulator that sits between the metal electrode and the semiconductor. Applying an electric field has an impact on the carriers in semiconductors. MIS structure is frequently seen in capacitive devices and semiconductor memory devices, and it is utilized as an isolation layer in transistors and integrated circuits. The insulator layer in the metal–insulator sandwich structures is usually bonded directly to a semiconductor surface and can be made of several materials, not just oxide. An oxide material such as SiO2, Al2O3, ZnO, or TiO2 is commonly employed as the insulator layer in metal–oxide–semiconductor (MOS) systems.1,2 Particularly in MOS transistors and integrated circuits, these structures are commonly used.

The formation of heterojunctions is the key to tuning the electronic and optoelectronic properties of various semiconductor devices. The formation and importance of semiconducting heterojunction devices based on metal oxides have been widely reported.3−5 TiO2 is a high-dielectric, high-refractive, big band gap material that is widely employed in many different electronic devices, especially in the memory, photovoltaic, and optical coatings industries.6,7 It is being investigated in several papers for application at the MS interface to provide barrier modification in addition to the semiconductor layer’s surface passivation. Before Schottky metallization, a TiO2 thin-film layer deposition provides several technological benefits, including enhanced device impedance characteristics and shielding the semiconductor surface from defective interfacial compounds.8,9 In other words, because of potential interfacial reactions resulting from the deposition of a rectifying metal contact, TiO2 can be added to the MS interface to control the defective states. Consequently, efforts are focused on improving the rectification capabilities and increasing the junction barrier in these kinds of diodes.10,11

Atomic layer deposition (ALD) is one of the most viable ways to successfully create TiO2 in diode applications, even if there are other methods used to deposit TiO2 thin-film layer at the MS interface, such as vapor deposition and solution-based techniques.12−17 It can produce dense, smooth films with fewer flaws and controllability over the film thickness when utilized in the deposition of TiO2 layers. Aydın et al.18 investigated the electrical analysis of the Al/p-Si Schottky diode with TiO2 thin film performed at room temperature. They concluded that the Schottky effect was found to be dominant in the reverse direction. A researcher19 studied the diode parameters of the Al/TiO2/p-Si Schottky diode at a wide temperature range and different illuminance intensities. With the increasing temperature, the ideality factor value of the device decreases from 4.878 to 2.305 and the barrier height increases from 0.287 to 0.714 eV. The electrical characterization of the Al/ALD-grown TiO2/p-Si structure was investigated by Karabulut et al.20 The optoelectronic properties of Li:TiO2-based photodiodes were investigated.21 It was concluded that the lowest n value of 5.92 is obtained for a 2% Li-doped diode. The I–V measurements of Al/TiO2/n-Si were taken in the temperature range of 50 K–400 K.22 The results showed that the currents of the devices are a strong function of the temperature. Yıldız et al. fabricated the Al/TiO2/p-Si Schottky-type by atomic layer deposition (ALD) for a thin layer and investigated I–V–T properties.23 Boutelala et al.24 obtained the characteristic parameters of Al/TiO2/p-Si/Al from I–V measurement. It was concluded that the diode exhibits perfect photosensitivity and high photoresponse properties. Additionally, TiO2 is typically utilized in the UV light detection spectrum. TiO2 nanorods were produced using the hydrothermal technique by Gao et al.25 Nicolaescu et al.26 created a heterostructured p–n type photodetector with high responsivity performance by thermal oxidation of n-TiO2 and using p-CuMnO2 to get n-TiO2/p-CuMnO2 thin film. TiO2 is occasionally employed as an interfacial layer to improve the photodetection capabilities of Schottky-type photodetectors in the presence of sunlight.27−30 The device performed well in the UV and visible ranges if TiO2 is placed on the Si substrate to create a photodetector.31 The effect of laser patterning (LP) on Schottky diode properties and graphene film quality was investigated by Orhan et al.32 They showed that laser patterning reduces reverse-biased leakage currents and increases the Schottky barrier height. In particular, they have seen how the laser patterning process affects 3D graphene nanosheets, resulting in the formation of new structures over the entire surface of the p-type substrate. These structures were in the form of nanospheres and nanoroses. According to their results, it is expected that the ideality factor and the barrier height will be improved after the laser patterning structuring and that the device will work effectively.

This study is focused on investigating the effect of the LP process on the diode properties of ALD-grown TiO2/p-type Si Schottky structures. By comparison of two diodes consisting of oxide (TiO2) junctions with an LP diode and a non-LP diode at 300 K in the dark, the effect of LP on the TiO2-p-type Si interface was evaluated. In this study, only the central region of the p-type Si wafer was patterned by LIPSS. The TiO2 layer was deposited directly on p-type Si with patterned and nonpatterned regions by the ALD technique for the fabrication of Al/ALD-grown TiO2/p-type Si Schottky diodes. Current–voltage (I–V) characteristics were measured in the dark at 300 K at ±5 V. Using the methods of Cheung and the standard TE theory, the ideality factor (n), the barrier height (ϕb), and the series resistance (Rs) of the fabricated diodes were extracted.

2. Experimental Section

In this work, we employed a p-type Si (100) wafer with a resistivity of 1–10 Ω·cm and a thickness of 380 μm. The p-type Si wafer was cleaned using Radio Corporation of America (RCA) techniques to get rid of any organic residues before processing.33 The central region of p-type Si was patterned by using a femtosecond laser source. A central region of p-type Si was patterned by only the LIPSS technique, but the whole wafer was coated with a TiO2 layer by the ALD technique. The laser source (up to 2 μJ pulse energy; ∼300 fs pulse duration) was a homemade fs-fiber laser with a 1 MHz rep rate at 1030 nm. After the laser was focused on the Si substrate, a Galvo scanner was used to raster-scan the area, which measured 8 × 8 mm2. On Si, the beam diameter was about ∼9 μm. The overlap factor was 5–6 pulses per spot, and the surface pulse energy was 400 nJ. A scanning electron microscopy (SEM) images of the laser patterned p-type Si wafer are shown in Figure 1. As can be seen in Figure 1, this results in a regular periodic path. In this study, two diodes with TiO2 layer laser pattern (LP) and nonlaser pattern (non-LP) were created. The I–V characteristics of the two diodes were measured in the ±5 V range at 300 K and in the dark. Using sputtering systems operating at 500 °C and 4.7 × 10–6 Torr pressure, 128 nm thick Al (99.999%) metal was formed to create an ohmic contact on the unpolished back surface of the plate. An ALD device (Okyay Nanotech) was used to deposit a TiO2 layer as a 16 nm thin film on the entire surface of the p-type Si wafer, including both laser-patterned and nonlaser-patterned regions. This was carried out at 170 °C, a low substrate temperature. To reach a layer thickness of 16 nm at a growth rate of 1.29 Å/cycle, 125 cycles of TiO2 deposition were carried out. Tetrakis (dimethylamido) titanium(IV) (TDMAT) and H2O were used as precursor materials of TiO2. To separate precursor cycles, nitrogen (%99.999) was employed as a cleaning gas and carrier at a flow rate of 7 sscm. The percussive temperature is 150 °C; the circle inner temperature is 170 °C, and the system pressure is 2.72 × 10–1 Torr. A 100 ms TDMAT pulse, a 20 s N2 purge, a 15 ms H2O pulse, and a 10 s N2 purge make up a single TiO2 ALD cycle. Subsequently, using a mask shaped like 1.5 mm circular dots, 128 nm thick Al (∼99.999%) rectifier contacts were formed on the TiO2 layer using the sputtering process at 7.06 × 10–6 Torr.

Figure 1.

Figure 1

Open in a new tab

SEM images of laser-patterned p-type Si wafer.

Figure 2 displays the measurement setup and schematic cross-section of the Al/ALD-grown TiO2/p-type Si diode. Keithley 2400 programmable constant current source was used for current–voltage (I–V) measurements. All of these measurements were carried out by controlling the device with the help of an IEEE-488 AC/DC converter card plugged into the computer. All of the electrical data presented in the study was collected from both the LP diode and the non-LP diode. In this study, only the central region of the p-type Si wafer was patterned by LIPSS. The TiO2 layer was deposited directly over the entire region, including patterned and nonpatterned regions, using the ALD technique to fabricate Al/ALD-grown TiO2/p-type Si Schottky diodes on p-type Si.

Figure 2.

Figure 2

Open in a new tab

(a) Measurement setup. (b) Schematic sections of Al/ALD-grown TiO2/p-type Si for LP (central region) and non-LP diode (edge region).

Figure 3 shows the energy band diagram for the Al/TiO2/p-type Si diode. The electron affinities of p-Si, anatase phase TiO2, and l metal have been reported to be approximately 4.05,34 4.2,18,35 and 4.3 eV,36 respectively.

Figure 3.

Figure 3

Open in a new tab

Energy band diagram of Al/ALD-grown TiO2/p-type Si diode.

3. Results and Discussion

First, the TE theory has been used to analyze the electrical properties of the Al/ALD-grown TiO2/p-type Si diode. The relationship between the current flowing through a Schottky diode and the forward bias voltage (V > 3kT/q) is as follows, for the TE theory.37

3. 1
3. 2

where I0 is the saturation current found at V = 0 at the (ln I)–V plot’s straight-line intercept. A* is Richardson’s constant (32 A/(cm2 K2) for p-type Si). The electron charge, Boltzmann’s constant, and temperature in Kelvin are denoted by the letters q, k, and T. The diode area, effective barrier height, and applied voltage are denoted by the letters A, ϕb, and V, respectively.

Using eq 3, the slope of the semilogarithmic I–V plots for the linear region was used to get the values of n.37

3. 3

ϕb can be derived from eq 4 as given by

3. 4

Figure 4 shows the (ln I)–V characteristics of an Al/ALD-grown TiO2/p-type Si diode at ±5 V and 300 K. The diode’s I–V curve is displayed in the embedded graph in Figure 4. ϕb values were calculated from the intercepts of the forward bias (ln I)–V plot at 300 K.

Figure 4.

Figure 4

Open in a new tab

Semilogarithmic I–V characteristics of the Al/ ALD-grown TiO2/p-type Si diode.

Figure 4 makes it clear that despite low leakage, the I–V characteristics of the Al/ALD-grown TiO2/p-type Si structure exhibit rectifying behavior. The diode’s rectification ratio (RR) was found to be 9.5 × 103. In the linear region, which is the forward bias I–V characteristic downward curvature, Rs is considerable. But in both the nonlinear and linear regions of I–V characteristics, the other two factors, n and ϕb, are important. A method created by S.K. Cheung and N.W. Cheung was used to calculate the values of n, ϕb, and Rs.37 For a nonlinear high-voltage region of the forward bias of I–V plots, Cheung’s model is implemented.38 According to this method, n, ϕb, Rs, and H(I) can be written as

3. 5
3. 6
3. 7

The ϕb was obtained from the linear region in the forward bias I–V characteristics. In Figure 5, the dV/d ln I vs I and H(I) vs I plots are presented for an Al/ALD-grown TiO2/p-type Si diode at 300 K, respectively.

Figure 5.

Figure 5

Open in a new tab

dV/d(ln I) vs I and H(I) vs I characteristics of Al ALD-grown TiO2/p-type Si diode.

The slope of the dV/d(ln I) vs I curve yields the value of Rs, while the curve’s cut-point yields the value of n. Using the n value in eq 5, Rs is obtained from the slope of the H(I) vs I curve and ϕb values are obtained from the intersection point of the curve in eq 7. The values of n, ϕb, and Rs for the Schottky diode are computed, as shown in Table 1. For Al/ALD-grown TiO2/p-type Si, the diode parameters for the LP and non-LP regions are given in Table 1.

Table 1. Diode Parameters for the LP Diode and the Non-LP Diode.

 
 LP diode
 Non-LP diode
Methods n Φb (eV) Rs (kΩ) n Φb (eV) Rs (kΩ)
TE 4.10 0.68 - 8.13 0.51  
Cheung dV/d ln I vs I 3.68 - 2.99 4.97 - 0.80
  H(I) vs I - 0.69 1.93 - 0.38 0.73
Open in a new tab

It was found that the n values were obtained as 4.10 and 3.68 from the TE method and Cheung functions for the LP diode, respectively. The Φb values were found as 0.68 and 0.69 eV from the TE method and Cheung functions, respectively. For the non-LP diode, the n values were obtained as 8.13 and 4.97 from the TE method and Cheung functions, respectively. The Φb values were found as 0.51 and 0.38 eV from the TE method and Cheung functions for the non-LP region, respectively. The results in Table 1 show a good agreement (1% discrepancy) between the barrier height (Φb) values obtained by the TE and Cheung methods. This confirms the effectiveness of these techniques. However, there is a discrepancy of about 10% between the nanovalues obtained by the two methods for the LP region. An increase in Rs values for the LP region is attributed to the defects and surface roughness created on p-type Si by laser patterning. The nonideal behavior (n > 1) of the diode confirmed the presence of interfacial states. The Φb values for all two methods are in agreement with each other for the LP-diode.

The periodicity of LIPSS on silicon for the laser used (1030 nm) is around 850–900 nm. Therefore, this periodicity is greater than the thickness of the TiO2 layer (16 nm) and the metal contact (128 nm) and it can be said that the layers will take the shape of the pattern during deposition. As a result, the effective contact surface of metal contacts is expected to increase compared with the flat surface. Laser patterning resulted in an increase in the Φb values and a decrease in the n values. After laser patterning, it was observed that the device worked effectively and the ideality factor and barrier height values were improved. Therefore, this effect may confirm an improvement in the functioning of the device. For comparison with our work, we have presented the diode parameters of various Schottky diodes with TiO2 interlayers of different thicknesses fabricated by some researchers18−24 at 300 K in the literature in Table 2.

Table 2. Comparison of Diode Parameters for Various Types of Schottky Diodes with TiO2 Interlayer.

Diodes Interlayer Coating Methods n (LP diode Φb (eV) RR References
Al/TiO2 (16 nm)/laser-patterned p-Si ALD 4.10 (TE) 0.68 9.5 × 103 Present work
3.68 (Cheung) 0.69
Al/TiO2 (200 nm)/p-Si ALD 2.96 (TE) 0.66 - (18)
2.55 (Cheung) 0.76
Al/TiO2 (20.4 nm)/p-Si Thermal evaporation 2.437 0.68 1.77 × 103 (19)
Al/TiO2 (10 nm)/p-Si ALD 1.04 0.80 - (20)
Al/TiO2/p-Si Sol–gel spin coating 9.41 0.76 4.75 × 103 (21)
Al/TiO2 (200 nm)/n-Si Spin coating 1.93 (TE) 0.93 2.49 × 104 (22)
2.26 (Cheung) 0.84
Al/TiO2 (4 nm)/p-Si ALD 12.71 (TE) 0.64 - (23)
12.73 (Cheung) 0.68
Al/bilayer TiO2 (226.92 nm)/p-Si Spin coating 1.91 0.71 3 × 104 (24)
Open in a new tab

As can be seen from Table 2, the thickness of the interlayer and the difference in the method used to create the measurements affected the n and Φb values. When the basic diode parameters of the device created in this study were compared with other studies, especially ALD-grown structures [refs (18), (20), and (23)], we found a high n value (8.13) for the non-LP diode as in ref (23) (see Table 1). The height of the barrier was found to be compatible with the study mentioned above at 6%.23 After laser pattering, the n value (calculated by the TE method) of the LP diode decreased by a factor of 50%. Compared to the structure grown by ALD by the researchers,20 the n values for the LP diode are higher than that of the work. As no RR data exist for the ALD-grown TiO2 structure, it could not be compared. The RR was higher than those of thermally evaporated19 and sol–gel spin-coated21 structures. A high RR value was obtained for the spin-coated bilayer TiO2 structure22 as shown in Table 2.

4. Conclusion

In this study, the electrical properties of the Al/ALD-grown TiO2/p-type Si Schottky barrier diode fabricated in the form of a heterojunction were examined in the dark and at 300 K using TE theory and Cheung methods. To create a thin layer of TiO2 on both the LP region and the non-LP region on the p-type Si substrate, the ALD technique was used in the study. The I–V characteristics of the diode were investigated. The presence of interfacial states was confirmed by the nonideal behavior (n > 1) of the measured values. It can be said that the layers will take the shape of the pattern during deposition. Thus, laser patterning increased the effective contact surface of metal contacts compared to the flat surface, causing an increase in the Φb values and a decrease in the n values. After laser patterning, it was observed that the device worked effectively and the ideality factor and barrier height values were improved. Therefore, this effect may confirm the improvement in the functioning of the device. This study provides insight into the fabrication and the electrical properties of heterojunction devices based on TiO2.

Acknowledgments

The authors are grateful to Gazi University Scientific Research Council (BAP) for the financial support of this research under Project Number FGA-2022-8252 (E.O.).

Data Availability Statement

The data that support the findings of this study are available from the corresponding author, [E.O.], upon reasonable request as it is unpublished data for another study.

This study was funded by the Scientific Research Council of Gazi University (BAP) Grant Number FGA-2022-8252. Open access is funded by The Anatolian University Libraries Consortium (ANKOS) in Türkiye.

The authors declare no competing financial interest.

References

  1. Efil E.; Kaymak N.; Seven E.; Orhan E. O.; Bayram O.; Ocak S. B.; Tataroglu A. Current-voltage analyses of Graphene-based structure onto Al2O3/p-Si using various methods. Vacuum 2020, 181, 109654. 10.1016/j.vacuum.2020.109654. [DOI] [Google Scholar]
  2. Kaymak N.; Efil E.; Seven E.; Tataroǧlu A.; Bilge S.; Orhan E. Ö. Electrical characteristics analyses of zinc-oxide based MIS structure grown by atomic layer deposition. Materials Research Express 2019, 6 (2), 026309. 10.1088/2053-1591/aaeded. [DOI] [Google Scholar]
  3. Wang J.; Bi J.; Xu Y.; Niu G.; Liu M.; Stempitsky V. Effects of charge trapping on memory characteristics for HfO2-based ferroelectric field effect transistors. Nanomaterials 2023, 13 (4), 638. 10.3390/nano13040638. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Akay D.; Seven E.; Gökmen U.; Bi̇lge Ocak S. Semiconducting Double-Layer Lead Monoxide Tin Oxide Nanostructures for Photodetectors. ACS Applied Nano Materials 2023, 6 (19), 17482–17490. 10.1021/acsanm.3c02610. [DOI] [Google Scholar]
  5. Seven E.; Akay D.; Ocak S. B.; Orhan E. Ö. Characterization of electrical parameters in PbO/SnO2 double layer semiconductor (DLS) diodes. Materials Science in Semiconductor Processing 2024, 169, 107913. 10.1016/j.mssp.2023.107913. [DOI] [Google Scholar]
  6. Türk Ç. G.; Tan S. O.; Altındal Ş.; İnem B. Frequency and voltage dependence of barrier height, surface states, and series resistance in Al/Al2O3/p-Si structures in wide range frequency and voltage. Physica B: Condensed Matter 2020, 582, 411979. 10.1016/j.physb.2019.411979. [DOI] [Google Scholar]
  7. Yıldırım M. Characterization of the framework of Cu doped TiO2 layers: An insight into optical, electrical and photodiode parameters. J. Alloys Compd. 2019, 773, 890–904. 10.1016/j.jallcom.2018.09.276. [DOI] [Google Scholar]
  8. Arslan E.; Bütün S.; Ozbay E. Leakage current by Frenkel-Poole emission in Ni/Au schottky contacts on Al0.83In0.17N/AlN/GaN heterostructures. Appl. Phys. Lett. 2009, 94 (14), 142106. 10.1063/1.3115805. [DOI] [Google Scholar]
  9. Yildirim M.; Kocyigit A. A Systematıc study on the dıelectrıc relaxatıon, electrıc modulus and electrıcal conductıvıty of Al/Cu:TiO2/n-Si (MOS) structures/capacıtors. Surf. Rev. Lett. 2020, 27 (10), 1950217. 10.1142/S0218625X19502172. [DOI] [Google Scholar]
  10. Aydin S. B.; Yildiz D. E.; Çavuş H. K.; Şahingöz R. ALD TiO2 thin film as dielectric for Al/p-Si Schottky diode. Bulletin of Materials Science 2014, 37, 1563–1568. 10.1007/s12034-014-0726-6. [DOI] [Google Scholar]
  11. Alialy S.; Altındal Ş.; Tanrıkulu E.; Yıldız D. E. Analysis of temperature dependent current-conduction mechanisms in Au/TiO2/n-4H-SiC (metal/insulator/semiconductor) type Schottky barrier diodes. J. Appl. Phys. 2014, 116 (8), 083709. 10.1063/1.4893970. [DOI] [Google Scholar]
  12. Kınacı B.; Özçelik S. Analysis of the temperature dependence of the capacitance-voltage and conductance-voltage characteristics of Au/TiO2 (rutile)/n-Si structures. Journal of electronic materials 2013, 42, 1108–1113. 10.1007/s11664-013-2524-0. [DOI] [Google Scholar]
  13. Pakma O.; Serin N.; Serin T.; Altındal Ş. On the energy distribution profile of interface states obtained by taking into account of series resistance in Al/TiO2/p-Si (MIS) structures. Physica B: Condensed Matter 2011, 406 (4), 771–776. 10.1016/j.physb.2010.11.078. [DOI] [Google Scholar]
  14. Bengi A.; Aydemir U.; Altındal Ş.; Özen Y.; Özçelik S. A. comparative study on the electrical characteristics of Au/n-Si structures with anatase and rutile phase TiO2 interfacial insulator layer. J. Alloys Compd. 2010, 505 (2), 628–633. 10.1016/j.jallcom.2010.06.095. [DOI] [Google Scholar]
  15. Bonkerud J.; Zimmermann C.; Weiser P. M.; Aarholt T.; Verhoeven E. F.; Vines L.; Monakhov E. V.; Herklotz F. Fabrication and characterization of Schottky barrier diodes on rutile TiO2. Materials Research Express 2020, 7 (6), 065903. 10.1088/2053-1591/ab9777. [DOI] [Google Scholar]
  16. Seven E.; Orhan E. Ö.; Di Bartolomeo A.; Ertuǧrul M.; Taştekin N. A. Graphene/Al2O3/Si Schottky diode with integrated waveguide on a silicon-on-insulator wafer. Indian Journal of Physics 2024, 10.1007/s12648-023-03062-7. [DOI] [Google Scholar]
  17. Candan İ.; Özen Y. Comparison of TiO2 and ZnO electron selective layers on the inverted-type polymer solar cells. Polym. Bull. 2021, 78, 3117–3129. 10.1007/s00289-020-03271-8. [DOI] [Google Scholar]
  18. Aydin S. B.; Yildiz D. E.; Çavuş H. K.; Şahingöz R. ALD TiO2 thin film as dielectric for Al/p-Si Schottky diode. Bulletin of Materials Science 2014, 37, 1563–1568. 10.1007/s12034-014-0726-6. [DOI] [Google Scholar]
  19. Sevgili Ö. Termal Buharlaştırma Yöntemiyle Hazırlanan Al/TiO2/p-Si Schottky Diyotun Elektriksel Özelliklerinin Sıcaklık ve Aydınlanma Şiddetine Baǧlı İncelenmesi. Türk Doǧa ve Fen Dergisi 2021, 10 (1), 275–283. 10.46810/tdfd.934492. [DOI] [Google Scholar]
  20. Karabulut A.; Orak İ.; Türüt A. The photovoltaic impact of atomic layer deposited TiO2 interfacial layer on Si-based photodiodes. Solid-State Electron. 2018, 144, 39–48. 10.1016/j.sse.2018.02.016. [DOI] [Google Scholar]
  21. Ruzgar S. The Optoelectrical Properties of Li: TiO2/p-Si Photodiodes for Various Li Doping. physica status solidi (a) 2020, 217 (23), 2000481. 10.1002/pssa.202000481. [DOI] [Google Scholar]
  22. Erdal M. O.; Kocyigit A.; Yıldırım M. Temperature dependent current-voltage characteristics of Al/TiO2/n-Si and Al/Cu: TiO2/n-Si devices. Materials Science in Semiconductor Processing 2019, 103, 104620. 10.1016/j.mssp.2019.104620. [DOI] [Google Scholar]
  23. Yıldız D. E.; Kocyigit A.; Yıldırım M. Comparison of Al/TiO2/p-Si and Al/ZnO/p-Si photodetectors. Opt. Mater. 2023, 145, 114371. 10.1016/j.optmat.2023.114371. [DOI] [Google Scholar]
  24. Boutelala A.; Bourfa F.; Mahtali M. Effect of light on electrical and photoelectrical characteristics of Al/TiO2/p-Si Schottky diode. Journal of Materials Science: Materials in Electronics 2020, 31 (14), 11379–11389. 10.1007/s10854-020-03687-y. [DOI] [Google Scholar]
  25. Gao Y.; Xu J.; Shi S.; Dong H.; Cheng Y.; Wei C.; Zhang X.; Yin S.; Li L. TiO2 nanorod arrays based self-powered UV photodetector: heterojunction with NiO nanoflakes and enhanced UV photoresponse. ACS Appl. Mater. Interfaces 2018, 10 (13), 11269–11279. 10.1021/acsami.7b18815. [DOI] [PubMed] [Google Scholar]
  26. Nicolaescu M.; Bandas C.; Orha C.; Şerban V.; Lazǎu C.; Cǎprǎrescu S. Fabrication of a UV photodetector based on n-TiO2/p-CuMnO2 heterostructures. Coatings 2021, 11 (11), 1380. 10.3390/coatings11111380. [DOI] [Google Scholar]
  27. Orak I.; Kocyigit A.; Turut A. The surface morphology properties and respond illumination impact of ZnO/n-Si photodiode by prepared atomic layer deposition technique. J. Alloys Compd. 2017, 691, 873–879. 10.1016/j.jallcom.2016.08.295. [DOI] [Google Scholar]
  28. Yıldırım M.; Kocyigit A. Characterization of Al/In: ZnO/p-Si photodiodes for various In doped level to ZnO interfacial layers. J. Alloys Compd. 2018, 768, 1064–1075. 10.1016/j.jallcom.2018.07.295. [DOI] [Google Scholar]
  29. Erdal M. O.; Yıldırım M.; Kocyigit A. A comparison of the electrical characteristics of TiO2/p-Si/Ag, GNR-TiO2/p-Si/Ag and MWCNT-TiO2/p-Si/Ag photodiodes. Journal of Materials Science: Materials in Electronics 2019, 30, 13617–13626. 10.1007/s10854-019-01731-0. [DOI] [Google Scholar]
  30. Banerjee D.; Asuo I. M.; Pignolet A.; Cloutier S. G. Low-cost photodetector architectures fabricated at room-temperature using nano-engineered silicon wafer and sol-gel TiO2-based heterostructures. Sci. Rep. 2019, 9 (1), 17994. 10.1038/s41598-019-54481-8. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Chatzigiannakis G.; Jaros A.; Leturcq R.; Jungclaus J.; Voss T.; Gardelis S.; Kandyla M. Laser-microstructured ZnO/p-Si photodetector with enhanced and broadband responsivity across the ultraviolet-visible-near-infrared range. ACS Applied Electronic Materials 2020, 2 (9), 2819–2828. 10.1021/acsaelm.0c00492. [DOI] [Google Scholar]
  32. Orhan E. O.; Efil E.; Bayram O.; Kaymak N.; Berberoǧlu H.; Candemir O.; Pavlov I.; Ocak S. B. 3D-graphene-laser patterned p-type silicon Schottky diode. Materials Science in Semiconductor Processing 2021, 121, 105454. 10.1016/j.mssp.2020.105454. [DOI] [Google Scholar]
  33. Bilge Ocak S.; Selcuk A. B.; Aras G.; Orhan E. Electrical analysis of Al/ZnO/p-Si, Al/PMMA/p-Si and Al/PMMA/ZnO/p-Si structures: comparison study. Materials Science in Semiconductor Processing 2015, 38, 249–256. 10.1016/j.mssp.2015.04.030. [DOI] [Google Scholar]
  34. Sze S. M.; Li Y.; Ng K. K.. Physics of semiconductor devices; John Wiley & Sons: 2021. [Google Scholar]
  35. Cai X.; Zhang P.; Wei S.-H. Revisit of the band gaps of rutile SnO2 and TiO2: A first-principles study. Journal of Semiconductors 2019, 40 (9), 092101. 10.1088/1674-4926/40/9/092101. [DOI] [Google Scholar]
  36. Gullu H. H.; Yildiz D. E. Capacitance, conductance, and dielectric characteristics of Al/TiO2/Si diode. J. Mater. Sci: Mater. Electron 2021, 32, 13549–1356. 10.1007/s10854-021-05931-5. [DOI] [Google Scholar]
  37. Wang Z. L. Zinc oxide nanostructures: growth, properties and applications. J. Phys.: Condens. Matter 2004, 16 (25), R829. 10.1088/0953-8984/16/25/R01. [DOI] [Google Scholar]
  38. Cheung S.; Cheung N. Extraction of Schottky diode parameters from forward current-voltage characteristics. Applied physics letters 1986, 49, 85–87. 10.1063/1.97359. [DOI] [Google Scholar]

Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Data Availability Statement

The data that support the findings of this study are available from the corresponding author, [E.O.], upon reasonable request as it is unpublished data for another study.

Articles from ACS Omega are provided here courtesy of American Chemical Society

RESOURCES