The Structuring of Glass and Silicon

From the viewpoint of the mechanical characteristics, glass and silicon resemble each other. They have a similar mechanical hardness, are brittle as they lack plasticity and are thus prone to fracture. Of the standard precision engineering procedures available for shaping, only those that do not use a geometrically defined cutter can be used, such as grinding and lapping. Microengineering techniques are much more efficient, but they do prove difficult for deeper structures. 

Structuring by Means of Masked Etching As in Microsystems Technology 

The mask, or reticle, used in photohthography is a layer of glass or transparent polymer coated with certain absorber structures. For microelectronics, there are procedures available, which can achieve much higher resolution. See Refs [2-4] for more details. 

The means of masking will be described together with the structuring processes for which they are used. 

To produce through-holes and cavities in a wafer, special forms of hthography are employed. If it is assumed that a roughly constant amount of material requires to be removed from all over the wafer, the creation in one and the same process of both cavities and holes is not feasible. The only possibility to achieve this is to perform 

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