Farklı kapı oksitli RadFET dozimetrelerinin ışınlama öncesi elektriksel karakteristiklerinin TCAD benzetim programı ile değerlendirilmesi

Yıl 2017, , 1258 - 1265, 01.12.2017

Ayşegül Kahraman Ercan Yılmaz

https://doi.org/10.16984/saufenbilder.337279

Öz

Bu çalışmanın amacı, kapı oksiti
yüksek-k’lı dielektriklerden oluşan RadFET dozimetrelerinin ışınlama öncesi
eşik gerilimlerini belirlemek ve sonuçları, kapı oksiti SiO₂’den
oluşan geleneksel sensörlerle kıyaslamaktır. Ayrıca çalışmada, farklı
konsantrasyonlu, derinlikli ve genişlikli p⁺ bölgelerinin
RadFET’lerin elektriksel karakteristiği üzerine etkileri de incelenmiştir. Bu
amaçla, dozimetrelerin duyar bölgeleri olarak 400 nm kalınlığında yüksek-k’lı
Al₂O₃, HfO₂ dielektrikleri ve SiO₂
kullanılmıştır. Sensörler, Silvaco TCAD benzetim programında tasarlanmıştır. p⁺
bölgelerinin uzunlukları, I_d-V_g karakteristiğini
değiştirirken, bu bölgelerin derinlikleri ve belirli bir değere kadar
konsantrasyonları elektriksel karakteristikte önemli bir rol oynamamıştır. SiO₂,
Al₂O₃ ve HfO₂-RadFET’lerden elde edilen en
düşük eşik voltajları sırasıyla, -5.22, -3.63 ve -3.10 V olarak bulunmuştur. Bu
sonuçlar, yüksek-k dielektrikli RadFET’lerin, radyasyon testlerinin yapılması
koşuluyla, daha geniş ölçülebilir doz aralığı açısından yeni nesil dozimetreler
için gelecek vaat eden bir aday olduğunu göstermektedir.

Anahtar Kelimeler

RADFET, TCAD, Yüksek-k, Eşik voltajı

Evaluation of the pre-irradiation electrical characteristics of the RadFET dosimeters with diverse gate oxides by TCAD simulation program

Öz

The aim of the present study is to
determine the pre-irradiation threshold voltages of the RadFET dosimeters with
gate oxide composed of high-k dielectrics and compare the results with the
traditional sensors, the gate oxide of which is composed of SiO₂.
The effects of the p⁺ regions with different concentration, depth
and length on the electrical characteristic of the RadFETs were also
investigated in the study. For these purposes, Al₂O₃, HfO₂
high-k dielectrics and SiO₂ with the thicknesses of 400 nm were used
as the sensitive regions of the dosimeters. The sensors were designed in the
Silvaco TCAD simulation program. While the lengths of the p⁺ regions
changed the I_d-V_g characteristics of the RADFETs, the
depths and concentrations until a certain value of these regions did not play
an important role in electrical characteristic. The lowest threshold voltages
obtained from the SiO₂, Al₂O₃ and HfO₂-RadFETs
were found to be -5.22, -3.63, and -3.10 V, respectively. These results
demonstrated that RadFETs with high-k dielectrics may be promising candidate
for the new generated dosimeters in terms of broader measurable dose range
providing their radiation tests. 

Anahtar Kelimeler

RADFET, TCAD, High-k, Threshold voltage

Kaynakça

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