These terms are presumably intended to refer either to all aorist passives and future passives, or possibly to just the ones with a theta, a.k.a. "first aorist passives" and "first future passives".
Most verbs form their aorist passive and future passive with -θη-, e.g. ἐλύθην, λυθήσομαι. But some form them with just -η-, e.g. ἐφάνην, φανήσομαι. The thetaful forms are sometimes called "first" and the thetaless ones "second" aorist/future passives. Without seeing the context, it's hard to guess whether "θη-future"/"θη-aorist" are supposed to refer to both these sets of forms or just the former.