Developing Photoresist on Silicon Samples

The listed method discussed the process of developing photoresist on silicon samples. There are two families of photoresist, positive and negative.

Positive resist:

A positive photoresist is a type of photosensitive material that becomes more soluble in a developer solution when exposed to light. The exposed areas of the photoresist are dissolved by the developer solution, leaving behind a patterned layer on the substrate. Here are some examples of positive photoresists and their applications:

1. Shipley 1805: This positive photoresist is commonly used in the production of printed circuit boards (PCBs). It is applied to a copper-clad substrate and then exposed to ultraviolet light through a photomask, which defines the pattern of the circuit. The exposed areas of the photoresist are then developed using an alkaline developer solution, leaving behind a pattern of copper traces on the substrate.
2. AZ 5214E: This positive photoresist is used in the production of microelectromechanical systems (MEMS) and other microfabrication applications. It can be patterned with high resolution using a mask aligner or direct laser writer and then developed with an alkaline developer solution to create complex microstructures.

Negative resist:

A negative photoresist is a type of photosensitive material that becomes less soluble in a developer solution when exposed to light. The unexposed areas of the photoresist are dissolved by the developer solution, leaving behind a patterned layer on the substrate. Here are some examples of negative photoresists and their applications:

1. SU-8: This epoxy-based negative photoresist is commonly used in the production of microfluidic devices, optical components, and other microfabricated structures. It can be patterned using a mask aligner or direct laser writer, and then developed with a combination of solvent and thermal treatment to create high aspect ratio structures.
2. MA-N1400: This negative photoresist is used in the production of microelectromechanical systems (MEMS) and other microfabrication applications. It can be patterned with high resolution using a mask aligner or direct laser writer and then developed with an alkaline developer solution to create complex microstructures.

Method:

This is a method for developing photoresist on silicon samples and typically involves the following steps:

1. Cleaning the substrate: The substrate, which is the material on which the photoresist will be applied, must be thoroughly cleaned to remove any dust, dirt, or other contaminants that could interfere with the adhesion of the photoresist.
2. Applying the photoresist: The photoresist is applied to the substrate using a spin-coating or spray-coating process. The substrate is rotated or sprayed with the photoresist solution, which is then allowed to dry.
3. Exposing the photoresist: The photoresist is exposed to ultraviolet light through a mask or patterned template that defines the areas where the photoresist will be selectively removed. The light causes a chemical reaction in the photoresist that makes it soluble in a developer solution in the exposed areas.
4. Developing the photoresist: The substrate is immersed in a developer solution. This dissolves the exposed areas of the photoresist, leaving behind a patterned layer on the substrate. The developer solution may be an alkaline such as MF319, depending on the type of photoresist used.
5. Rinsing and drying: The substrate is rinsed with deionized water. This removes any remaining developer solution and then dried to prepare it for further processing.

Time savings with samply

Samply sample holders can be used to perform this development on mass. A samply 100 for example can develop 20 samples in parallel. If the development of one sample takes 1 minute and rinse/dry takes a further minute. The total processing time for 20 samples will be 40 minutes. Loading 20 samples into the samply 100 takes less than 2 minutes with 1 minute development and rinse/dry. There are significant time savings to have.

The exact process of developing photoresist can vary. It depends on the specific application and the type of photoresist used. These steps provide a general overview of the process.

Samply sample holders are compatible with a large range of chemicals listed in this compatibility chart.

The range of samply sample holders is designed to fit into standard lab beakers (25ml, 50ml, 100ml) eg Fischer.

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