DETERMINING CAPTURE CROSS SECTION FROM CAPTURE TRANSIENT SIGNALS

Öz

The characterization of defect levels within a semiconductor using capacitive methods is based on manipulating the width of the depletion region through pulsed biasing. During the measurement, the processes of charge emission and subsequent charge capture at the defect energy levels occur sequentially. The aim of this study is to investigate defect energy levels by analyzing both charge capture and emission processes and to determine the capture cross section using the capture capacitance transient signal. In this study, a method is proposed where the capture cross section could be calculated directly from the capture capacitance transient signals. The charge capture process occurs in two distinct regions, known as the fast and slow capture regions, with the slow capture region becoming dominant under specific conditions. In this study, the activation energy of the defect level in the boron-doped Si sample was determined to be in the range of 0.159–0.216 eV using the Deep Level Transient Spectroscopy (DLTS) method. The capture cross section was determined as an average of σ_n=1.03×10^(-16) cm^2 from the capacitance transient signals of the charge emission process. In contrast, when using the capture capacitance transient signals, the average value of the capture cross section was calculated as 5.62×10^(-11) cm^2.

Anahtar Kelimeler

• Capture Cross Section
• Defect
• DLTS
• Trap

YAKALAMA GEÇİŞ SİNYALLERİNDEN YAKALAMA KESİT ALANINI BELİRLEME

Öz

Yarıiletken içerisindeki kusur seviyelerinin kapasitif yöntemlerle karakterizasyonu, arınmış bölge genişliğinin pulslu beslemeler ile manipüle edilmesine dayanır. Ölçüm sırasında, kusur enerji seviyelerinde yük yayınımı ve ardından yük yakalanması ardışık süreçler olarak gerçekleşir. Bu çalışmanın amacı, hem yük yakalama hem de yayınlama süreçlerini analiz ederek kusur enerji seviyelerini araştırmak ve yakalama kapasite geçiş sinyalini kullanarak yakalama tesir kesit alanını belirlemektir. Bu çalışmada, yakalama tesir kesit alanının doğrudan yakalama kapasite geçiş sinyalinden hesaplanabileceği bir yöntem önerildi. Yük yakalama süreci, hızlı ve yavaş olmak üzere iki farklı bölgede gerçekleşmekte olup, belirli koşullar altında yavaş yakalama bölgesi baskın hale gelmektedir. Bu araştırmada kullanılan boron katkılı Si örneğin kusur seviyesinin aktivasyon enerjisi, Derin Seviye Geçiş Spektroskopisi (DLTS) yöntemi kullanılarak 0.159-0.216 eV aralığında belirlenmiştir. Yük yayınlama sürecine ait kapasite geçiş sinyallerinden yakalama tesir kesit alanı ortalama σ_n=1.03×10^(-16) cm^2 olarak hesaplanmıştır. Buna karşılık, yakalama kapasite geçiş sinyalleri kullanıldığında, yakalama tesir kesit alanının ortalama değeri 5.62×10^(-11) cm^2 olarak hesaplanmıştır.

Anahtar Kelimeler

• DLTS
• Kusur
• Tuzak
• Yakalama Tesir Kesit Alanı

Kaynakça

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