Evaluation of Defects in CdTe Using a Simple Cathodoluminescence Technique

Abstract

normalCdTe has a low luminescence efficiency and its surface readily deteriorates by electron or photon excitation at the power levels generally required to perform spatially resolved cathodoluminescence (CL) or photoluminescence scanning. Previous CL studies employed a sophisticated mirror system to provide the necessary collection efficiency to image defects in normalCdTe . In this paper, we demonstrate a simple high collection efficiency CL technique using a solid‐state photodiode within the sample chamber of a scanning electron microscope. A comparison is made of the patterns formed by the CL dark spots and the etch features produced by a known defect etchant.

Spatially Resolved Cathodoluminescence Study of Semi‐Insulating GaAs Substrates

“…A Si photodiode, placed in close proximity to the sample, was used to detect the CL radiation. [5,6] In contrast to the experimental arrangement of Kitahara et al, [4] the high collection efficiency of this detectorsample arrangement allows integral CL images of samples at room temperature even when the luminescence efficiency of the sample is relativ.ely low. The --~5 cm diameter, Cr-doped, SI GaAs substrates were grown by the liquid encapsulated Czochralski (LEC) technique along the <100> direction.…”

Metallurgical Behavior of Gold‐Based Ohmic Contacts to the InP / InGaAsP Material System

“…For samples where the interaction depth could not be resolved on the cleaved edge, cylinder-lapped cross-sectional samples (15) were prepared and stained. To show that features observed on cleaved edges were not an artifact of the cleaving procedure, cathodoluminescence (CL) imaging was used (16). In the CL mode of the scanning electron microscope (SEM), a low CL efficiency is expected for regions of the semiconductor affected by the alloying.…”