| Title |
|
|
|
Compositional analysis based upon electron holography and a chemically sensitive reflection
| |
| Author |
|
|
|
| |
| Abstract |
|
|
|
| We present a method for compositional analysis of low-dimensional semiconductor heterostructures. The suggested procedure is based upon electron holography and the exploitation of the chemically sensitive (002)-reflection that is available in sphalerite type material. We apply an off-axis imaging condition where the strongly excited (002)-beam is centred on the optic axis. From the centred sideband of the hologram we use the phase of the (000)-beam and the modulus of the amplitude of the chemically sensitive (002)-reflection to evaluate the local composition and the local specimen thickness in an iterative and self-consistent way. The application of the procedure is demonstrated using an AlAs/GaAs(001) superlattice with a nominal period of 5 nm and a layer thickness of 2.5 nm. The concentration profile was fitted with a segregation model from which we obtain a superlattice period of (4.86 +/- 0.03) nm, a total amount of AlAs of (2.5 +/- 0.2) nm per AlAs layer and a segregation efficiency of R=0.51 +/- 0.02. |
| |
| Language |
|
|
|
English
| |
| Source (journal) |
|
|
|
CONFERENCE SERIES- INSTITUTE OF PHYSICS | |
| Source (book) |
|
|
|
Royal-Microscopical-Society Conference on Microscopy of Semiconducting, Materials, MAR 25-29, 2001, UNIV OXFORD, OXFORD, ENGLAND | |
| Publication |
|
|
|
Bristol : Iop publishing ltd, 2001
| |
| ISBN |
|
|
|
0-7503-0818-4
| |
| Volume/pages |
|
|
|
169(2001), p. 33-36
| |
| ISI |
|
|
|
000176465200007
| |
|