Stable and metastable phase equilibria of the In-Se system

The In-Se phase diagram was redetermined using DTA, x-ray analysis, optical microscopy, TEM, and scanning electron microscopy. In9Se11 and In5Se7 are stable phases at stoichiometric composition and beta In2Se3 was observed at 59.6 at.% Se. beta In2Se3 decomposes at 198 degrees C into gamma In2Se3 an d In5Se7. Alloy melts between 33 and 54 at.% Se exhibit a strong tendency f or undercooling. Between 50 and 60 at.% Se, the InSe,In6Se7, or In2Se3 phas es solidify directly from the undercooled melt, and the formation of In5Se7 and In9Se11 is suppressed while applying cooling rates between 2 to 10 K/m in. The respective undercooled states and metastable phase equilibria are p rovided.