MODSYMEL aims to develop a computer-controlled X-ray diffraction system capable of many different structural characterisations of semiconductor crystalline materials. The goal is to provide industry with an instrument for process control and quality checks in industrial conditions. The instrument will be modular, in that the attachments necessary for the different diffraction geometries will be interchangeable and require only minor operations to correct the primary X-ray beam alignment.
An instrument for process control and quality checks in industrial conditions has been developed, which is capable of handling up to 200 mm substrates. Computer aided modelling for the most suitable diffraction geometries has resulted in a versatile instrument concept, satisfying the production level analysis requirements of both silicon and compound semiconductor materials.
The overall instrument has been designed taking into account all the various measurement methods and allowing rapid changes in configuration without the need for time consuming and complex adjustments. Software controlled automated setup will ensure that the instrument is aligned. A sophisticated sample holder has been designed to handle up to 200 mm substrates. The partners have fabricated and tested the monochronometer, collimator and analyser crystals, as well as different beam conditioners. Writing the software for data evaluation is in progress.
The instrument measurement capabilities will include:
- strain evaluation in heteroepitaxial and multilayer structures
- analysis of the interface sharpness of deposited material
- absolute measurements of single-crystal lattice parameters
- depth profiles of lattice disorder
- deformation caused by semiconductor manufacturing processes
- characterisation of thin monocrystalline, polycrystalline and amorphous films down to 10 nm.
Each of these techniques has relevance to the measurement and control of processes at the leading edge of manufacturing.
Several demonstrators will be provided during the course of the project: the computer-controlled diffractometric system, various attachments for multicrystal diffraction, collimator and analyser crystals, and software packages for the collection and simulation of the experimental data.