Electron Field Emission from SiC/Si Heterostructures Formed by Carbon Implantation into Silicon and Etching of the Top S
- PDF / 543,237 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 112 Downloads / 166 Views
A6.7.1
Electron Field Emission from SiC/Si Heterostructures Formed by Carbon Implantation into Silicon and Etching of the Top Silicon Layer Yumei Xing1, Jihua Zhang1, Yuehui Yu1, Zhaorui Song1 and Dashen Shen2 1 Ion Beam Laboratory, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, P.R. China. 2 Department of Electrical and Computer Engineering, University of Alabama in Huntsville, Huntsville, AL 35899, U.S.A. ABSTRACT High intensity electron field emissions were obtained from SiC/Si heterostructures formed by high temperature carbon implantation into silicon and subsequently etching of the top silicon layer. Implantation processes were performed at 700 °C with a dose of 3.0 to 8.0 x 1017 ions/cm2. Post-implantation annealing in argon at 1250 °C for 5h was done for partial samples. β-SiC precipitates were easily formed and embedded in silicon at the interface of SiC/Si heterostructures during high temperature carbon implantation for all samples. The densely distributed small protrusions led to efficient electron emission. Implantation dose scarcely impacted the electron emission characteristics when it reached to a definite value. After annealing, the density of protrusions at the interface of SiC/Si heterostructures became smaller since β-SiC precipitates were grown into larger sizes, which caused to a relatively inefficient electron emission.
INTRODUCTION Recently, various carbon materials have received great attentions as cold cathode of electron field emission for flat panel displays. It is found that electron emission can occur at a much lower turn-on field with carbon materials than other materials. The carbon containing materials include carbon nanotubes [1], amorphous carbon [2,3], diamond and diamond-like films [4] and silicon carbide layers [5-8]. Due to excellent electronic and mechanical properties, SiC has attracted intensive research efforts [9,10]. In our previous research, a low turn-on field of 2.6 V/µm was obtained from SiC/Si heterostructures formed by carbon implantation into silicon at 700 °C and subsequently etching of the top silicon layer since SiC can act as a natural etch-stop layer [8]. After etching, densely distributed sharp tips were left on the surface of the SiC/Si heterostructure. Sharp tips are evidently favorable for electron emission, so time-consuming annealing treatment becomes unnecessary. Carbon implantation was processed at energies of 120 or 160 keV; implantation dose was changed from 3.0 to 8.0 x 1017 ions/cm2. Post-implantation annealing in argon at 1250 °C for 5h was performed, which was used to further clarify electron emission mechanism of the SiC/Si heterostructure in this research.
A6.7.2
EXPERIMENTAL DETAILS P-type (100) silicon wafers with resistivity of 5~9 Ω·cm were used as substrates for carbon implantation, which was performed in an ULVAC implanter with an energy of 120 or 160 keV. Substrates were kept at nominally 700 °C with the combination of ion beam and external heating during implantation. Impl
Data Loading...
