NEGATIVE PHOTORESISTS

A photoresist is a light-sensitive material used in several processes, such as photolithography and photoengraving, to form a patterned coating on a surface, which is crucial in the whole electronic industry. Resists may be classified either as positive or negative, depending on response to exposure.

When exposed to the UV light, the negative resist becomes crosslinked/polymerized, and more difficult to dissolve in developer. Therefore, the negative resist remains on the surface of the substrate where it is exposed, and the developer solution removes only the unexposed areas. Masks used for negative photoresists, therefore, contain the inverse or photographic negative of the pattern to be transferred.

UV Lithography

Negative tone photoresists effective for broadband and i-line exposure. A variety of viscosities are available for different film thicknesses in one spin-coating step. SU-8 series offer chemically amplified, epoxy based negative resists. Applications include lift-off patterning, and the manufacture of polymeric single-mode (SM) and multi-mode (MM) waveguides.

SU-8
SU-8 2000
SU-8 3000
KMPR 1000
ma-N 400 & ma-N 1400
EpoCore & EpoClad

E-Beam / Deep UV Lithography

Negative tone photoresists effective for e-beam or deep UV exposure. A variety of viscosities are available for different film thicknesses in one spin-coating step. Applications include electroplating, master/template manufacture, and etch mask.

ma-N 2400 & mr-EBL 6000
UVN 2300

Laser Direct Writing @ 405 nm

Negative tone photoresists effective for direct laser writing at 405 nm. A variety of viscosities are available for different film thicknesses in one spin-coating step. Applications include electroplating, master/template manufacture, and etch mask.