  We introduce two-dimensional topological insulators in proximity to
high-temperature cuprate or iron-based superconductors as high-temperature
platforms of Majorana Kramers pairs of zero modes. The proximity-induced
pairing at the helical edge state of the topological insulator serves as a
Dirac mass, whose sign changes at the sample corner because of the pairing
symmetry of high-$T_c$ superconductors. This sign changing naturally creates at
each corner a pair of Majorana zero modes protected by time-reversal symmetry.
Conceptually, this is a topologically trivial superconductor-based approach for
Majorana zero modes. We provide quantitative criteria and suggest candidate
materials for this proposal.
