Wet Etching Study of La0.67(Sr0.5Ca0.5)0.33MnO3 Films on Silicon Substrates

Abstract

Wet etching of colossal magnetoresistive (CMR) perovskite La 0.67 (Sr 0.5 Ca 0.5 ) 0.33 MnO 3 (LSCMO) films on Bi 4 Ti 3 O 12 /CeO 2 /yttrium-stabilized zirconia (YSZ)-buffered Si substrates was investigated using potassium hydroxide (KOH) and buffered hydrofluoric acid (BHF) solutions. X-ray diffraction (XRD) and scanning spreading resistance microscopy (SSRM) measurements revealed that the morphological roughness of the LSCMO films increases, while the electrical resistance roughness decreases, with increasing KOH etching time. The LSCMO films are highly chemically resistant to KOH solution; however, in the case of BHF etching, an etch rate of 22 nm/min was obtained with high selectivity over a photoresist mask.

Fabrication of $\hbox{La}_{0.7}\hbox{Sr}_{0.3} \hbox{MnO}_{3}$–Si Heterojunctions Using a CMOS-Compatible Citric Acid Etch Process

“…However, the etch rate was seen to increase by over two orders of magnitude when the solution was heated from room temperature up to 85 • C. Since temperatures above 90 • C are known to affect the reflow properties of resists typically used in silicon technology [17], [18], the maximum solution temperature in our experiments was limited to 85 • C, at which the maximum etch rate of the LSMO films was found to be ∼73 nm/min. This value was higher compared to the etch rate of LSMO using a 5:1 BHF solution, which we confirmed to be 30 nm/min, and in line with the values predicted earlier [13].…”

“…We note a distinct lacuna in processes developed to incorporate these novel sets of manganites in typical Si technology, particularly in the availability of a selective etchant for LSMO films on Si. Literature on wet etching of manganite films using buffered HF (BHF) [13] suggests BHF to be one such possible candidate since BHF does not etch silicon. However, BHF is known to etch SiO 2 at a rate of 100 nm/min and is commonly used as its wet etchant in silicon processing [14].…”

Low Temperature Epitaxial Oxide Ultrathin Films and Nanostructures by Atomic Layer Deposition

“…CeO 2 is a very attractive material widely known for its use in catalysis, energy storage systems, gas sensing, ultraviolet filtration, and polishing agent . Epitaxial growth of CeO 2 thin films has generated huge interest for silicon-on-insulator structures , and also as buffer layer in functional oxide heterostructures such as high temperature superconductors (HTS) coated conductors and microelectronic devices. − For most of these applications, slight changes in film thickness, composition, degree of epitaxy, or the presence of defects can dramatically affect the system properties. Preparation of epitaxial (doped)-CeO 2 films has been achieved by several physical ,, and chemical deposition techniques. , In particular, atomic layer deposition (ALD) is a unique chemical gas-phase deposition technique where the film growth proceeds through self-limiting surface reaction achieved through alternate pulsing of the precursors. , This ensures excellent large-area uniformity and conformity and enables simple and atomic layer control of film thickness and composition.…”

Thermal and Optoelectrical Analysis of La0.7Sr0.3MnO3 Thin Film Thermistor in 8–12 μm Range for Uncooled Microbolometer Application

“…As a solution to the new industrial demand for better performance in the semiconductor industry, new functional oxides have been suggested for micro/nano device applications [1]. Typically known as rare-earth manganite oxides (Re1-xAexMnO3, where Re is a rare earth element like La, Nd, Pr and Ae is an alkaline earth element, e.g.…”