Three-dimensional electron probe roughness analysis of InP sidewalls processed by reactive ion beam etching

Abstract

A quantitative three-dimensional measurement of sidewall roughness of InP etched by chlorine-based reactive ion beam etching (RIBE) is presented. An electron probe surface roughness analyzer using four secondary electron detectors was employed. The minimum value of average sidewall roughness under the optimized etching condition was as small as 1 nm, where the etching condition was an ion extraction voltage of 400 V and a Cl2 gas pressure of 1.2×10−3 Torr. It is found that the etched sidewall roughness can be reduced by lowering ion extraction voltage with a relatively higher gas pressure.

Direct measurement of nanoscale sidewall roughness of optical waveguides using an atomic force microscope

“…However, a SEM-based measurement technique ͑electron probe roughness analyzer͒ has been utilized to obtain the roughness of an etched sidewall profile. 7 The method has an advantage as a noncontact measurement technique, but its resolution was limited to 1 nm. 7 An AFM has better sensitivity in characterizing planar surface morphology than SEM, but it is difficult to use in measuring the vertical surface of three-dimensional ͑3-D͒ structures.…”

“…7 The method has an advantage as a noncontact measurement technique, but its resolution was limited to 1 nm. 7 An AFM has better sensitivity in characterizing planar surface morphology than SEM, but it is difficult to use in measuring the vertical surface of three-dimensional ͑3-D͒ structures. This is especially true where the 3-D structures consist of small geometries.…”

Estimation of Arterial Stiffness by Time–Frequency Analysis of Pulse Wave

“…In the past, an SEM-based measurement technique for line edge roughness (LER) was used to characterize the roughness of etched sidewalls [6]. This technique defines the edge roughness using a line demarcated by the point extending furthest from the sidewall at each position along the line.…”

Study of roughness evolution during reactive ion etching

“…SEM-based measurement technique using electron probe roughness analyzer has been utilized to obtain the roughness of an etched sidewall profile. This technique was advantageous as it is non-contact measurement technique and sample damage can be prevented; however, its resolution was limited to 1 nm [53]. AFM is well suited for the measurement of surface roughness in the nanometer scale and is better than SEM, but it is difficult to use to measure the vertical surface of three-dimensional (3-D) structures due to the reasons above.…”