Two-Beam Photoacoustic Analysis of ZnSe/GaAs Grown by MOCVD

Abstract

검출기로써 압전소자(PZT)를 사용한 two-beam여기 광음향 분광시스템을 써서 narrower-bandgap 물질 GaAs 기관위에 생장된 wider-bandgap 물질 ZnSe 의 광학적 성질을 조사하였다. 시료는 ZnSe 결정의 원료 물질로써 dimethylzine 와 diethylselenide를 써서 유기화합물 기상반응법(MOCVD)으로 p-, n-, 및 반절연성 GaAs(100)기판위에 생장시킨 것이다.

광음향 스펙트럼은 ZnSe 의 bandgap 에너지 근처에서 sharp dip 을 보였다. 광음향 신호의 세기는 기판의 전도형에 의존하였다.

A two-beam excitation photoacoustic spectroscopy (PAS) system with a piezoelectric transducer (PZT) as the detector has been utilized in the study of the optical properties of a wider-bandgap material ZnSe grown on a narrower-bandgap material GaAs substrate. Samples were grown by metal organic chemical vapor deposition (MOCVD) using dimethylzinc and diethylselenide as source materials of ZnSe crystal on p-, n-, and semi-insulating GaAs(100).

The photoacoustic spectra have a sharp dip near the bandgap energy of ZnSe. The intensity of the PA signal is highly dependent on the conduction type of the substrate.

A two-beam excitation photoacoustic spectroscopy (PAS) system with a piezoelectric transducer (PZT) as the detector has been utilized in the study of the optical properties of a wider-bandgap material ZnSe grown on a narrower-bandgap material GaAs substrate. Samples were grown by metal organic chemical vapor deposition (MOCVD) using dimethylzinc and diethylselenide as source materials of ZnSe crystal on p-, n-, and semi-insulating GaAs(100).

The photoacoustic spectra have a sharp dip near the bandgap energy of ZnSe. The intensity of the PA signal is highly dependent on the conduction type of the substrate.