Free-standing yttria-stabilized zirconium oxide membranes were fabricated by means of two different processes which are compatible with the standard complementary metal oxide semiconductor technology. The membrane is a thin film suspended on a pyramid-shape hole obtained on a silicon substrate by means of an anisotropic etching. A square membrane with a maximum side dimension of 170 mu m was obtained. (C) 1999 Elsevier Science S.A. All rights reserved.