The Role of Self-Assembly Monolayers (SAM) on Schottky Diode Performance

Yıl 2025, Cilt: 13 Sayı: 1, 357 - 371, 30.01.2025

Adem Mutlu , Cem Tozlu , Mustafa Can

https://doi.org/10.29130/dubited.1530876

Öz

This study investigates the electrical and charge transport properties of Schottky diodes with a p-Si/TiO2/SAM/Al structure, incorporating the self-assembly monolayers (SAMs) 4", 4""-[biphenyl-4,4" diylbis(phenylimino)]dibiphenyl-4-carboxylic acid (MZ187) onto a titanium dioxide (TiO2) layer synthesized via the sol-gel method. The impact of the MZ187 molecule on diode performance was evaluated based on parameters such as the barrier height (∅b), ideality factor (n), and series resistance (Rs). Experimental results reveal that the MZ187 monolayers on TiO2 substantially enhanced diode performance, reducing the n from 3.7 for the control diode to 2.7 for the MZ187-modified diode. The Rs was also significantly reduced, while the ∅b increased. The rectification ratio increased from 1.3x102 for the control diode to 2.2x103 for the MZ187 modified diode. These improvements are attributed to the ability of MZ187 molecules to minimize interface states (Nss) and improve surface quality. These findings underscore the critical role of SAMs in optimizing Schottky diode performance and demonstrate how the MZ187 molecule enhances diode efficiency by altering interface properties. The effectiveness of SAM coatings in enhancing Schottky diode performance makes a significant contribution to the field of nanoelectronics. This research paves the way for future studies on the use of SAMs in various nano
electronic applications and offers promising potential for improving the performance and reliability of these technologies.

Anahtar Kelimeler

Schottky diode, sol-gel TiO2, self-assembly monolayer, electrical characterization, interfaces, surface modification

Kendiliğinden Organize Olan Tek Tabaka Moleküllerin (SAM) Schottky Diyot Performansı Üzerindeki Rolü

Öz

Bu çalışma, p-Si/TiO2/SAM/Al yapısına sahip Schottky diyotlarının elektriksel ve yük taşıma özelliklerini incelemektedir. Schottky diyotları, sol-jel yöntemiyle sentezlenen titanyum dioksit (TiO2) tabakasına, kendiliğinden organize olan monolayer (SAM) molekülü olan 4",4" "-[bifenil-4,4-diylbis(fenilimino)]dibifenil-4-karboksilik asit (MZ187) uygulanarak üretilmiştir. MZ187 molekülünün
diyot performansı üzerindeki etkisi, idealite faktörü (n), seri direnci (Rs) ve bariyer yüksekliği (∅b) gibi
parametreler üzerinden değerlendirilmiştir. Deneysel sonuçlar, TiO2 üzerinde monolayer MZ187 kaplamasının diyot performansını önemli ölçüde iyileştirdiğini göstermektedir. Kontrol diyot için 3.7 olan n, MZ187 modifiye diyot için 2.7'ye düşmüştür. Rs, MZ187 nedeniyle azalmış ve ∅b artmıştır. Doğrultma oranı, kontrol diyot için 1.3x102'den MZ187 modifiye diyot için 2.2x103'e yükselmiştir. Bu iyileşmeler, MZ187 moleküllerinin arayüzey durumlarını (Nss) minimize etme ve yüzey özelliklerini geliştirme yeteneğine atfedilmektedir. Bu çalışma, SAM'ların Schottky diyot performansını optimize etmedeki kritik rolünü vurgulamakta ve MZ187 molekülünün arayüzey özelliklerini değiştirerek diyot verimliliğini nasıl iyileştirdiğini göstermektedir. SAM kaplamalarının Schottky diyot performansını artırmadaki etkinliği, nanoelektronik alanına önemli katkılar sağlamaktadır. Bu araştırma, SAM'ların çeşitli nanoelektronik uygulamalarda kullanımına yönelik gelecekteki çalışmalara temel oluşturmakta ve bu teknolojilerin performansını ve güvenilirliğini artırmada umut verici etkiler sunmaktadır.

Anahtar Kelimeler

Schottky diyot, sol-gel TiO2, kendiliğinden organize olan tek tabaka, elektriksel karakterizasyon, arayüzeyler, yüzey modifikasyonu

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