Ara yüzey seviyelerinin ve seri direncin Sc2O3 MOS kapasitörünün elektriksel karakteristiği üzerine etkisi

Abstract

 

Bu çalışmanın amacı, ara yüzey seviyelerinin ve seri direcin (R_s) Sc₂O₃ (Skandiyum oksit) MOS (Metal Oksit Yarıiletken) kapasitörünün elektriksel karakteristiği üzerine etkisini frekansa bağlı olarak incelemektir. Sc₂O₃ MOS kapasitörü RF magnetron saçtırma sistemi ile p tipi Si (100) üzerine üretilmiştir. Kapasitörün kapasitans-voltaj (C-V) ve iletkenlik-voltaj (G/ω-V) değişimleri, 50 kHz ile 1 MHz arasında değişen altı farklı frekansta ölçülmüştür. Elde edilen sonuçlar, C-V eğrisinin yığılım bölgesinde kapasitans değerlerinin R_s etkisi nedeniyle beklenenden daha düşük olduğunu göstermiştir. G/ω-V karakteristiklerinde ise bu etki nedeniyle pikler belirgin bir şekilde oluşmamıştır. Bu nedenle, ölçüm sonuçlarına R_s düzeltmesi yapıldıktan sonra, Sc₂O₃/Si ara yüzeyinde oluşan tuzak yüklerinin elektriksel karakteristik üzerine etkisi incelenmiştir. Frekansın azalmasıyla birlikte ara yüzey tuzak yükleri, AC voltaj sinyalini takip ederek ölçülen kapasitansa katkı sağlamışlardır. Düzeltilmiş C-V ve G/ω-V ölçümlerinden yararlanılarak p tipi Si için taşıyıcı konsantrasyonu (N_a), bariyer yüksekliği (Φ_B) ve Fermi seviyesi - değerlik bandı arasındaki enerji farkı (E_F) değerleri hesaplanmıştır.

The purpose of this study is to examine the effects of interface states and series resistance (R_s) on the electrical characteristic of Sc₂O₃ (Scandium oxide) MOS (Metal Oixde Semiconductor) capacitor depending on frequency. Sc₂O₃ MOS capacitor was produced on p type Si (100) with RF magnetron sputtering. Capacitance-voltage (C-V) and Conductance-voltage (G/ω-V) variations of the capacitor were measured in six different frequencies ranging from 50 kHz to 1 MHz. The obtained results showed that the capacitance values in the accumulation region of the C-V curve were lower than expected due to the R_s effect. The peaks were not clearly formed due to this effect in the G/ω-V characteristics. For this reason, the effect of trap charges on the electrical characteristics of the Sc₂O₃/Si interface was investigated after R_s correction applied to the experimental results. The interface trap-charges contributed to the measured capacitance with decreasing frequency by following the AC voltage signal. The carrier concentration for p type Si (N_a), barrier height (Φ_B), and energy difference between the bulk Fermi level and valance band edge (E_F) values were calculated by using corrected C-V and G/ω-V measurements.

Keywords

• yüksek-k,MOS,Sc2O3,Seri direnç,ara yüzey seviyeleri

Effects of interface states and series resistance on the electrical characteristic of Sc2O3 MOS capacitor

Abstract

The purpose of this study is to examine the effects of interface states and series resistance (R_s) on the electrical characteristic of Sc₂O₃ (Scandium oxide) MOS (Metal Oixde Semiconductor) capacitor depending on frequency. Sc₂O₃ MOS capacitor was produced on p type Si (100) with RF magnetron sputtering. Capacitance-voltage (C-V) and Conductance-voltage (G/ω-V) variations of the capacitor were measured in six different frequencies ranging from 50 kHz to 1 MHz. The obtained results showed that the capacitance values in the accumulation region of the C-V curve were lower than expected due to the R_s effect. The peaks were not clearly formed due to this effect in the G/ω-V characteristics. For this reason, the effect of trap charges on the electrical characteristics of the Sc₂O₃/Si interface was investigated after R_s correction applied to the experimental results. The interface trap-charges contributed to the measured capacitance with decreasing frequency by following the AC voltage signal. The carrier concentration for p type Si (N_a), barrier height (Φ_B), and energy difference between the bulk Fermi level and valance band edge (E_F) values were calculated by using corrected C-V and G/ω-V measurements. 

Keywords

• high-k,MOS,Sc2O3,series resistance,interface states

References

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