Wet thermal silicon oxide
Wet thermal oxide is used as mask layer for silicon wet and dry etching, as electrical isolation layer or as sacrificial layer for silicon surface micromachining. By means of standard steam oxidation, layers up to 3 microns of oxide are grown. Layer thickness variation in the batch and between batches is less than 5 %.
Silicon rich, low stress, LPCVD silicon nitride
Silicon rich, low stress LPCVD silicon nitride is applied
in thin micromechanical structures, where a little tensile stress is preferred.
There are optimized recipes for different layer thickness applied for:
- very thin membranes (50 nm, e.g. for TEM characterization applications),
- standard micromachined membranes, bridges, and cantilevers (1 µm)
Beside applications in micromachined structures, the layer can also be used as mask material, since it has an excellent chemical resistance for silicon wet etching (KOH). The total stress is tensile and lower than 300 MPa, depending on the layer thickness. Thickness variations within a batch are below ± 5 % around the average thickness. The average thickness is ± 5 % of the required thickness. For dedicated customized applications, this variation can be reduced.
Stoichiometric, optical, LPCVD silicon nitride
Stoichiometric LPCVD is applied for optical applications,
like on-chip wave-guides. As an alternative for this purpose, also thick
wave guide layer packages (up to 15 µm), of wet oxide, SiON, and
PECVD oxide sandwiches can be fabricated. These are offered together with
high qualified design and application knowledge of optical field experts.
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us for prices
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