Chalcogenide Random Access Memory (C-RAM) has shown significant promise in combining the desired attributes of an ideal memory, including: nonvolatility, fast read/write/erase speed, low read/write/erase voltage/power, high endurance, and radiation hardness. Current C-RAM production technology relies on sputtering to deposit the active chalcogenide layer. The sputtering process leads to difficulties in meeting requirements for device conformality (in particular – filling vias), film adherence, compositional control, wafer yield, and surface damage. Ultimately, a viable CVD manufacturing process is needed for high-density products to realize the full potential of C-RAM. In this work, we discuss the Metal-Organic Chemical Vapor Deposition (MOCVD) tool technology used to produce the films and report the materials properties of GeSbTe-based chalcogenide thin films grown in small research scale and in large production scale MOCVD reactors. Films were grown at low pressures at temperatures ranging from 350 C to 600 C. X-Ray Fluorescence (XRF) and Auger Electron Spectroscopy (AES) were performed and determined that the film composition is controllable and uniform.

Lead Zirconium Titanium Oxide (PZT) thin films were prepared at low temperature using a SMI Metal Organic Chemical Vapor Deposition SpinCVD TM tool. Films prepared by this technique were evaluated for multiple device applications. The low temperature PZT film process addresses problems with device manufacture encountered by techniques that rely on high thermal budgets to obtain superior materials properties. Film growth processes were developed based on the following criteria: low defect density, a high necked and dense microstructure, and highly uniform properties across the wafer. The growth process, ferroelectric film properties, and suitability for IR sensing and FRAM applications are discussed.

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Uniformly distributed ZnO nanowall network structures were grown at 550 degrees C by organometallic chemical vapor deposition technique on the GaN/sapphire substrate without using any catalysts. In this research, we discussed the nanostructures and optical properties of ZnO samples grown under the same conditions but on different underlying materials (GaN/sapphire and sapphire). By adjusting the growth parameters, ZnO nanowall networks with a honeycomb-like pattern without using any metal catalysts were successfully fabricated on the GaN/sapphire and sapphire substrates. Since the lattice mismatch between ZnO and GaN is only about 1.8% while the lattice mismatch between ZnO and sapphire is about 18.4%. Lattice mismatch may not be the decisive factor in the formation process of ZnO nanowall networks. The ZnO grown on GaN epilayer had smaller full width at half maximum value than that of ZnO grown under the same growth condition on the sapphire substrate, indicating a higher crystal quality in the sample of ZnO on GaN. The room temperature PL measurement of both ZnO nanostructures grown on GaN and sapphire show strong ultraviolet peak intensity and high intensity ratio of the near band emission to the deep-level emission in a PL spectrum.

Zinc oxide is attracting growing interest for potential applications in electronics, optoelectronics, photonics, and chemical and biochemical sensing, among other applications. We report herein our efforts in the growth and characterization of p-and n-type ZnO materials by metalorganic chemical vapor deposition (MOCVD), focusing on recent nitrogen-doped films grown using diethyl zinc as the zinc precursor and nitric oxide (NO) as the dopant. Characterization results, including resistivity, Hall measurements, photoluminescence, and SIMS, are reported and discussed. Electrical behavior was observed to be dependent on illumination, atmosphere, and heat treatment, especially for p-type material.