Progress in Epitaxial Oxides on Semiconductors
- PDF / 2,157,006 Bytes
- 12 Pages / 612 x 792 pts (letter) Page_size
- 10 Downloads / 200 Views
T3.1.1
Progress in Epitaxial Oxides on Semiconductors Z. Yu,* Y. Liang, H. Li, J. Curless, C. Overgaard, R. Droopad, Y. Wei, X. Hu, B. Craigo, J. Finder, K. Eisenbeiser, A. Talin, S. Smith, S. Voight, J. Wang, D. Marshall, D. Jordan, J. Edwards, Jr. and K. Moore Physical Sciences Research Laboratories – Motorola Labs, 7700 S. River Parkway, MD ML26, Tempe, AZ 85284, U.S.A. *[email protected] ABSTRACT In this paper, we review the recent progress in the area of epitaxial oxides on semiconductors at Motorola Labs. Critical issues such as surface preparation, initial nucleation and growth behaviors of SrTiO3 (STO) thin film epitaxy on Si(001) are addressed. Using a systematic approach, high-quality epitaxial STO films are successfully grown on semiconductor substrates such as Si, silicon-on-insulator (SOI) and Ge. Amorphous interfacial layer between the epitaxial STO and the semiconductor can be eliminated or tailored by controlling oxide growth process and parameters. STO-based metal-oxidesemiconductor (MOS) capacitors and transistors are fabricated and tested, in order to explore the potential of STO as high-k gate dielectrics for future generation CMOS transistor technology. In addition, high-quality STO epitaxial films are utilized as thin buffer layers for fabricating integrated oxide heterostructures on semiconductors. Various perovskite oxide films such as SrZrO3, LaAlO3 and Pb(Zr,Ti)O3 are deposited epitaxially on STO-buffered Si(001) for potential high-k gate dielectrics and surface-acoustic-wave (SAW) device applications. INTRODUCTION Metal oxides are very attractive for a variety of device applications. Various perovskite-type metal oxides (ABO3), in particular, have become a technologically important class of materials due to their unique dielectric, piezoelectric, ferroelectric, ferromagnetic, optical, electro-optic, and catalytic properties [1,2]. These perovskite oxides cover a wide range of materials from insulators to conductors and superconductors, and everything in between. It is extremely important and desirable to integrate these highly functional metal oxides with mature semiconductor technology. Successful heteroepitaxy of these metal oxides on semiconductors such as Si opens the door to a wide range of novel device technologies with enhanced functionality and flexibility. For example, one can design and fabricate integrated multi-functional epi-oxide heterostructures on Si for applications such as logic, non-volatile memories, filters, sensors and optical devices, etc. The key for high-quality oxide epitaxy on semiconductor is the ability to achieve coherent two-dimensional (2D) initial nucleation and subsequent epitaxial film growth. The general requirements for 2D nucleation and epitaxial growth include that: (1) there is a structure and/or lattice match between the film and the substrate, (2) the film energetically “wets” the substrate surface, i.e., the surface energy of the growing film plus the interface energy is lower than the substrate surface energy, (3) the growing surface is ther
Data Loading...
