Determination of the ion angular distribution for electron cyclotron resonance, plasma-etched HgCdTe trenches

Ion angular distribution (IAD) affects the width and aspect ratio in electron cyclotron resonance (ECR)-etched HgCdTe trenches. The IAD was determined by etching studies together with scanning electron microscopy (SEM) analysis. The results confirm that low-energy, large-angle ions contribute to the etching of the photoresist, while higher-energy, low-angle ions are responsible for HgCdTe etching. The HgCdTe ECR etching was further elucidated by sputter-bombardment theory. This model correctly predicts the nature and depth of the damage region in ECR-etched HgCdTe as well as the distribution and composition of the ejected material.