Numerical Modeling and Simulation of Various Metal/n-Si Contacts

Year 2022, Volume: 12 Issue: 1, 398 - 413, 15.06.2022

Osman Kahveci , Mehmet Fatih Kaya

https://doi.org/10.31466/kfbd.1081025

Cited By: 1

Abstract

In this study, various metal/semiconductor contact structures were simulated using Al, Mo, Cu and Ag metals and n-type Si semiconductor. The semi-logarithmic forward current-voltage characteristics of the contacts were obtained using thermionic emission theory between 0 to 0.25 V range. The barrier heights and ideality factors of the contact models were calculated depending on the work function of the metal. Lowest obstacle height is calculated in Al/n-Si contact model as 0.64 eV and the highest obstacle height is calculated in Ag/n-Si contact model as 0.82 eV. A meshing process was performed by dividing the contact models into separate volumetric cells. Thus, during the current conduction, the electron concentration of the surface, the hole concentration and the electrical potential changes along the contact geometry were simulated and the effects of different parameters were also examined by simulation of Schottky contact.

Keywords

Numerical Modelling, Schottky Barrier Height, Current–Voltage Characteristic, COMSOL

Farklı Metal/n-Si Kontakların Sayısal Olarak Modellenmesi ve Simülasyonu

Abstract

Bu çalışmada, Al, Mo, Cu ve Ag metalleri ile n-tipi Si yarıiletkeni kullanılarak farklı metal/yarıiletken kontak yapısı modellenmiştir. Kontakların 0-0.25 V aralığında ileri beslem yarı logaritmik akım-gerilim karakteristiği termiyonik emisyon teorisi kullanılarak elde edilmiştir. Kontak modellerin metalin iş fonksiyonuna bağlı olarak engel yükseklikleri ve idealite faktörleri hesaplanmıştır. En düşük engel yüksekliği 0.64 eV olarak Al/n-Si model kontak için, en büyük engel yüksekliği ise 0.82 eV olarak Ag/n-Si model kontak için hesaplanmıştır. Kontak modelleri ayrı hacimsel hücrelere bölünerek bir ağ oluşturma işlemi gerçekleştirilmiştir. Böylece akım iletimi sırasında, kontak geometrisi boyunca, yüzeyin elektron konsantrasyonu, hol konsantrasyonu ve elektriksel potansiyel değişimleri modellenerek farklı parametrelerin etkileri simule edilerek kontağın üzerindeki değişimleri incelenmiştir.

Keywords

Sayısal modelleme, Schottky Engel Yüksekliği, Akım-gerilim karakteristiği, COMSOL

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