Junction sharpness in field-induced transistor structures in CuxAg1−xInSe2

Abstract
We have measured the widths of the transition regions at pnp junctions that are formed on CuxAg1−xInSe2 by high electric field at room temperature, by using a scanning tunneling microscope with capacity for measuring current–voltage curves on physical contact. We find marked transition regions of low conductivity with widths in the range of 1.3–5 μm. This shows that the junction created by the electromigration mechanism in this material, while diffuse by the standards of those produced by high‐temperature or high‐energy methods, are remarkably sharp by solid‐state ionic measures.