Protective Coating

Overview of our Protective Coatings

! AZ 520 D phase out !

The manufacturer Merck informed us that the protective coating AZ 520 D will be phased out no later than end of 2021 (official statement).
Basically, the AZ 520 D is a photoresist without photoactive compound, which should make it comparable easy to find a suited alternative. We would be glad if you contact us to discuss your requirements on a protective coating, and assist in finding another resist from our portfolio, which could either be a standard low-cost photoresist, or another PAC-free resist.

We are very sorry about this decision from the manufacturer, and will do our best to allow you a smooth transfer to an alternative resist.
Technical help: tech(at)

AZ 520 D

Protective Coating

Thickness Range and Exposure

Film thickness: 1.5 ... 3.0 µm
UV-sensitivity: none
Sales volumes: 250 ml, 500 ml, 1.000 ml, 2500 ml und 5 Liter

Genral Information

AZ® PC 520 D is a cost-effective coating for the protection of device surfaces during operations such as back-lap or backside etch.It is based on Novolak resin, has a blue colour for easy inspection and is resistant to most etchants. The thickness of this coating is 2.0 µm at 4000 rpm spin speed.

Please note, that the protective coating AZ® 520D is not stable in KOH-etches typically used for silicon etching.

In the datasheet there is a reference to a product AZ® 546D this product was dicontinued in 2005 and is therefore no longer available. 

Technical Data Sheet:

For further information please refer to the technical data sheet:
> AZ® 520 D (TDS)

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