Abstract
The range profiles of low-energy (100 to 1500 eV) 3He and 4He atoms implanted in situ, parallel to the [110] direction (±5°) of tungsten, at 60 K have been measured employing an atom-probe field-ion microscope. The absolute depth of each deposited helium atom, from the irradiated surface, was measured directly to within one (110) interplanar spacing (27middot;24 Å). At 60 K both 3He and 4He were found, in other research, to be immobile; thus, the range profiles were determined in the complete absence of any diffusional effects. The mean range (α) of the 3He and 4He range profiles increases monotonically, although non-linearly, as the implantation energy was increased from 100 to 1500 eV; the value of x varies from 33 to 158 Å and from 19 to 195 Å for the 3He and 4He profiles, respectively. The straggling (Δx) of the 3He and 4He range profiles also increases monotonically, although non-linearly, as the implantation energy was increased from 100 to 1500 eV; the value of Δx varies from 23 to 97 Å and from 16 to 124Å for the 3He and 4He profiles, respectively. All of the 3He and 4He range profiles exhibit positive skewness; that is, they are skewed from a normal distribution.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 177-198 |
| Number of pages | 22 |
| Journal | Philosophical Magazine A: Physics of Condensed Matter, Structure, Defects and Mechanical Properties |
| Volume | 44 |
| Issue number | 1 |
| DOIs | |
| State | Published - Jul 1981 |
Funding
This research was supported by the U.S. Department of Energy. Additional support wa8 received from the National Science Foundation through the use of the technical facilities of the Materials Science Center at Cornell University.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- General Materials Science
- Condensed Matter Physics
- Physics and Astronomy (miscellaneous)
- Metals and Alloys