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

Bu çalışmada, RadFET'lerin kapı oksit tabakasına implante edilmiş B+ iyonlarının Vth 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 Vthdeğerleri, RadFET'lerin akım-gerilim (Id-Vg) karakteristiklerinden elde edilmiştir. Artan implantasyon enerjisi, Vth değerlerinin düşmesine neden olmuştur. Vth değerinin sıfır olması, daha geniş ölçülebilir doz aralığına sahip RadFET'lerin üretilmesi için önemlidir. Ancak, implantasyon enerjisindeki sürekli artışla birlikte Vth, p-kanalı oluşumu nedeniyle negatif voltaj değerlerinde gözlenmemiştir. 300 nm-RadFET için en düşük Vth değeri, 6.5×1011 iyon/cm2 bor dozu ve 72 keV'de, -1.082 V olarak bulunmuştur. 400 nmRadFET için bu değer, 2.3×1011 iyon/cm2 bor dozu ve 106 keV'de, -1.139 V olarak elde edilmiştir..

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

In this study, the effect of the B+ ions implanted to gate oxide layer of the RadFETs on Vth 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 Vthvalues were obtained from the current-voltage (Id-Vg) characteristics of the RadFETs before and after implantation. Increasing implantation energy caused the reduction of the Vth values. The zero Vth value is important to produce the RadFET with broader measurable dose range. However, Vth 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 Vth 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.

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