Photosensitive components
The p hoto sensitive components of our positive photoresists belong to the group of naphtho qu inone d iazides (NQD).
Cross linker
The patterning of negative resists is based on the stabilization of exposed areas in the presence of cross-linking agents. Radical starters like e.g. azo-bis(isobutyronitrile) (AIBN)
Storage and ageing
Photoresists are light-sensitive, their properties change in the presence of light or elevated temperatures. Resists age during storage and are therefore supplied in light-protected amber glass bottles,
Sensitive, etch-stable negative e-beam resist for processes without yellow light
The success story of electron beam lithography began in the 1980th with the development of the first PMMA resists. These resists are absolutely light-insensitive in the UV-wavelength range above 300 nm.
1. What are e-beam resists composed of, and how do they work?
E-beam resists (electron beam resists) are designed for electron beam and deep UV applications for the fabrication of highly integrated circuits, mainly for mask fabrication. They are employed in electron beam direct writing and multilayer processes.
2. For how long are e-beam resists stable, and what are the optimal storage conditions?
PMMA- and copolymer e-beam resists are not light-sensitive in the visible UV range, they consequently don’t react to light exposure (no safe yellow light required) and are substantially less temperature-
1. What are photoresists composed of, and how do they work?
Photoresists (also photo coatings) are primarily used in micro electronics and micro system technologies for the production of µm- and sub-µm structures. These resists are generally deposited by spin coating in a range between 250
3. What is the optimal pre-treatment of substrates for e-beam resist application?
If new and clean substrates (wafers) are used, a bake at approximately 200 °C for a few minutes is sufficient in order to dry the substrates, which however then have to be processed quickly.
2. For how long are photoresists stable, and what are the optimal storage conditions?
Photoresists are light-sensitive, they are affected by light exposure and high temperatures, and age-related changes occur during storage. Resists are therefore filled in light-protected amber glass bottles,
4. How high is the adhesion strength of e-beam resists to different wafers?
Adhesion between substrate and coating is a sensitive feature of a resists, which is also true for e-beam resists. PMMA- and copolymer resists are however significantly less prone for adhesion problems than e-