Silicon

Silicon wafers play an integral role in microfluidic chip manufacturing and can be used to prepare SU8 molds, silicon molds, and silicon runner chips.

SU-8 Mold

Silicon wafers are widely used in SU-8 Mold preparation.SU-8 photoresist is a polymer material with excellent mechanical properties and chemical stability, which can be used to fabricate microchannels and microstructures in microfluidic chips. The specific steps for the preparation of SU-8 Mold using dissected photoresist wafers are as follows:

1. Preparation of silicon wafer substrate: select high-purity silicon wafers as the substrate, and clean and treat them.

2. Coating photoresist: A layer of SU-8 photoresist is coated on the surface of the wafer and the structure to be prepared is exposed using a corresponding mask.

3. UV exposure: The exposed part of the wafer surface is subjected to UV exposure to cross-link and solidify the photoresist.

4. Stripping: The unexposed photoresist on the surface of the wafer is removed, exposing the area to be stripped.

5. Dissection: The area on the surface of the wafer to be stripped is chemically or mechanically stripped to separate it from the wafer substrate.

6. Cleaning: The wafer is cleaned to remove the remaining photoresist and stripping solution.

7. Drying: The silicon wafers are dried to remove water and residual solvents.

8. SU-8 Mold Preparation: The dissected wafer is used as a template for SU-8 Mold, coated with SU-8 photoresist, exposed to UV and dried, and finally SU-8 Mold is obtained.

Preparation of SU-8 Mold using profiled silicon wafers has the following advantages:

1. High precision: dissected optical wafer processing can produce tiny structures and devices with high precision and controllable size, which is suitable for the preparation of microchannels and microstructures in microfluidic chips.

2. Short preparation cycle: The process of preparing SU-8 Mold using dissected silicon wafers is relatively simple, and the preparation cycle is short, which is suitable for mass production.

3. Wide range of application: The dissected light wafer processing can be used to fabricate microchannels and microstructures of different shapes and sizes, with a wide range of applicability, allowing the preparation of SU-8 Molds of various shapes.

4. Good Repeatability: The dissected light wafer processing can realize mass production with good repeatability.

However, there are some limitations and challenges in profiling silicon wafers to prepare SU-8 Mold, for example:

1. The height of the prepared SU-8 Mold is limited by the thickness of the dissected silicon wafer, making it difficult to prepare taller structures and devices.

2. The process of dissecting requires the use of chemical stripping fluid or mechanical stripping tools, which may damage the surface of the formwork or cause deformation of the formwork, affecting the quality and accuracy of the formwork.

3. The processing of dissected wafers requires the use of expensive photolithography equipment and special stripping fluids, which are more costly.

4. The higher cost of profiled wafer processing is suitable for mass production, but less suitable for small batch production or personalized customization needs.

In conclusion, profiling silicon wafers in SU-8 Mold preparation is an effective method to prepare high-quality and accurate microstructures and microchannels, but it is necessary to consider its limitations and challenges and select the appropriate processing method and process flow.

Silicon Mold

Microfluidic Chip Silicon Mold is a commonly used mold for fabricating microfluidic PDMS chips, which enables high depth-to-width ratio flow paths through a deep silicon etching process. It is important to note that pure silicon molds, which cannot be used directly for pouring PDMS, require superhydrophobic treatment of the silicon wafer.

silicon microfluidic chip

Silicon wafers are also a common material for the preparation of microfluidic chips. Flow channels are formed on silicon wafers by a deep silicon etching process, and then an anodic bonding process realizes the bonding of silicon and glass to form closed flow channels.