Sr_2Rh_(1-x)Ru_xO_4 (0 ≤ x ≤ 1) composition-spread film growth on a temperature-gradient substrate by pulsed laser deposition

摘要

K_2NiF_4-type Sr_2Rh_(1-x)Ru_xO_4 (0 ≤ x ≤ 1) composition-spread films were fabricated on (LaAlO_3)_(0.3)-(Sr_2AlTaO_6)_(0.7) (LSAT) substrate by using the combinatorial PLD method. From a temperature spread combinatorial deposition, Sr_2RhO_4 (x = 0) is found to grow epitaxially only in a narrow temperature range, i.e. 735 +- 15℃. By varying the composition and temperature along x and y axes of the substrate, respectively, two-dimensional (2D) libraries of Sr_2Rh_(1-x)Ru)xO_4 (0 ≤ x ≤ 1) films were fabricated to map the growth temperature dependence of film crystallinity for the full range of x = 0-1. The optimum epitaxial growth temperature exhibited clear dependence on the compositional variation, x. From measurements of the electric conductivity of the films, metal-insulator-metal transitions were detected as the compositional parameter x increased from 0 to 1.