Fig. 7
From: Fabrication of ion-trap electrodes by self-terminated electrochemical etching
The dependence of etching current on the immersion depth. The red open circles are measurements of 0.5 mm rods with 7 V etching voltage. The green open circles corresponds 1.0 mm rods with 7 V. The red solid dots corresponds 0.5 mm rods with 3 V. The green solid circles corresponds 1 mm rods with 3V. The fitted curves for 7V are linear while the fitted curves for 3V are logarithmic