FARKLI B+ İMPLANTASYON KOŞULLARI İÇİN RADFET’LERİN ELEKTRİKSEL KARAKTERİZASYONUNUN TCAD BENZETİM PROGRAMI İLE İNCELENMESİ

Yıl 2017, Cilt 22, Sayı 2, 53 - 64, 20.08.2017

Ayşegül KAHRAMAN Ercan YILMAZ

https://doi.org/10.17482/uumfd.335425

Öz

Bu çalışmada, RadFET’lerin kapı oksit tabakasına implante edilmiş B⁺ iyonlarının V_th üzerine etkisi, Silvaco TCAD benzetim programı ile incelenmiştir. 300 nm ve 400 nm kalınlıklarında kapı oksite sahip RadFET’ler, tüm üretim adımları TCAD’e tanıtılarak tasarlanmıştır. İmplantasyon öncesi ve sonrası V_th değerleri, RadFET’lerin akım-gerilim (I_d-V_g) karakteristiklerinden elde edilmiştir. Artan implantasyon enerjisi, V_th değerlerinin düşmesine neden olmuştur. V_th değerinin sıfır olması, daha geniş ölçülebilir doz aralığına sahip RadFET’lerin üretilmesi için önemlidir. Ancak, implantasyon enerjisindeki sürekli artışla birlikte V_th, p-kanalı oluşumu nedeniyle negatif voltaj değerlerinde gözlenmemiştir. 300 nm-RadFET için en düşük V_th değeri, 6.5×10¹¹ iyon/cm² bor dozu ve 72 keV’de, -1.082 V olarak bulunmuştur. 400 nm-RadFET için bu değer, 2.3×10¹¹ iyon/cm² bor dozu ve 106 keV’de, -1.139 V olarak elde edilmiştir.

Anahtar Kelimeler

RadFET, Üretim benzetimi, B+ implantasyonu, Eşik gerilimi, TCAD

Investigation of Electrical Characterization of RadFETs For Dİfferent B+ Implantation Conditions With TCAD Simulation Program

Öz

In this study, the effect of the B⁺ ions implanted to gate oxide layer of the RadFETs on V_th was investigated by Silvaco TCAD simulation program. The RadFETs with the gate oxide thicknesses of 300 nm and 400 nm were designed by introducing the all of the RadFETs production steps to TCAD. The V_th values were obtained from the current-voltage (I_d-V_g) characteristics of the RadFETs before and after implantation. Increasing implantation energy caused the reduction of the V_th values. The zero V_th value is important to produce the RadFET with broader measurable dose range. However, V_th was not observed in the negative voltages with continuous increment in the implantation energy due to the p-channel formation. For the 300 nm-RadFET, the lowest V_th value was found as -1.082 V for boron dose with 6.5×10¹¹ ions/cm² at 72 keV. This value for 400 nm-RadFET was obtained as -1.139 V for boron dose with 2.3×10¹¹ ions/cm² at 106 keV.

Anahtar Kelimeler

RadFET, TCAD, Production simulation, B+ implantation, Threshold voltage, TCAD

Kaynakça

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