Supersymmetric Tuned Inflation

We address an issue what kind of tuning realizes a flat potential for inflaton in supergravity. We restrict ourselves to the case that inflationary dynamics is not affected by separate supersymmetry-breaking effects, and consider examples of a single chiral superfield as an inflaton with its vacuum of the vanishing cosmological constant. The examples potentially include the cases of Polonyi field or right-handed sneutrino as an inflaton.