Thanks for the post! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?
dielectric constant (ε) of semiconductor can be changed by deposition on high (or low) ε substrate.
==> Dielectric confinement is effective reduction of the dielectric constant due to the penetration of electric field into barrier medium with a small dielectric constant.
for further inf.
Keldysh, L.V.: Pis’ma Zh. Eksp. Teor. Fiz. 29, 716 (1979). JETPLett. 29, 658, 1979