CombiLab


Introduction

We have been involved in a new type of material development strategy called “Combinatorial Materials Exploration (CME)” in collaboration with Dr. Chikyow of the National Institute of Materials Science (NIMS), Tsukuba, Japan. CME as a new research approach to explore an extremely large multi-variant materials space is rapidly becoming a new paradigm for accelerated materials research by enabling both screening and understanding complex material systems in a time- and cost-effective manner. Systematic variance of properties with material’s composition or processing parameters yields information on nanoscale mechanisms underlying structure-property relationships; for example changing average valence or atomic separation. Successful application of CME to critical problems in the microelectronics area facilitates further advancement of inorganic materials science programs as a whole.

Recent support from the Micron Foundation and the National Science Foundation has allowed for the creation of a new CME laboratory (CombiLab) at the University of Washington. This page describes some of the key equipment that makes up that lab.

Deposition and Growth

Atomic Layer Deposition (ALD) Chamber. ALD grows thin films through a cyclic process of introducing reactive precursor gases and purging the chamber. This process is iterated until the film is the desired thickness. The ALD Chamber is currently used to deposit Strontium Titanium Oxide dielectric films. The ALD chamber is connected to the MBE and XPS chambers allowing sample transfer under vacuum conditions.
Molecular Beam Epitaxy (MBE) Chamber. MBE is the preferred method of depositing very low defect concentration films. Our MBE chamber is used for the deposition of metal electrodes on the surface of STO samples. The MBE chamber is connected to the ALD and XPS chambers allowing sample transfer under vacuum conditions.
RF Sputtering Chamber. This chamber is devoted to deposition of thin oxide films (most recently, lanthanum manganites and ITO). It has a 200W RF power supply, a 2" magnetron sputtering target, and a sample holder capable of reaching ~550 C.
Inkjet Printer. This tool allows for patterned deposition of solution-based films on a variety of substrates. Printing parameters such as drop volume and velocity can be controlled by the user to allow for use with solutions of varying viscosity.

Characterization

X-Ray Photoelectron Spectrometer (XPS). XPS provides elemental and chemical information about film surfaces (~1-10nm depth). This XPS system uses an Al K-alpha x-ray incident beam, and collects electrons with an SSL-300 Hemispherical Analyzer. The XPS chamber is attached to the MBE and ALD chambers, allowing in situ analysis of clean thin films.
Bruker D8 X-ray Diffractometer (XRD). XRD allows for determination of crystal structure and phase identification. The Bruker D8 features a high-power (4.8 kW) rotating anode Cu K-alpha x-ray source, a single Goebel mirror, and a beam collimator to provide a beam spot size of 500 to 50 microns diameter. X-rays are detected with a multiwire area detector. Samples are held in Eulerian cradle with a 4-circle geometry.
Siemens D5000 X-ray Diffractometer (XRD). The Siemens D5000 is optimized for powder, bulk and thin film samples. X-rays are generated by a Cu K-alpha tube source (2.2 kW) and pass through a Goebel mirror, removing the K-beta signal. Optional attachments include a graphite monochromator, and a grazing incidence / X-ray reflectometry attachment.

Additional equipment

Veeco Stylus Profilometer. For measuring film thickness and surface roughness.
Box furnaces. To 1200 C.
Rapid thermal annealer (RTA). IR lamp RTA allows for heating rates up to 50 C /s. Annealing possible in vacuum, air, or inert atmosphere.
Various Custom Characterization Equipment. To measure thermal, electric, and magnetic properties.