Photolithography Process 

Photolithography is one of the most important microfabrication processes used to manufacture integrated circuits, MEMS devices, microfluidic chips, photonic components, biosensors, and semiconductor devices. UniversityWafer supplies silicon wafers, quartz, fused silica, glass, sapphire, thermal oxide, and silicon nitride substrates optimized for photolithography, photoresist patterning, wet and dry etching, and advanced research applications.

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Silicon Wafers for Two-Step Photolithography

UniversityWafer supplies silicon wafers for photolithography, two-step lithography, photoresist patterning, wet etching, dry etching, through-etch processing, MEMS, microfluidics, and semiconductor research. Researchers commonly use 100 mm P-type <100> SSP silicon wafers when dopant type and resistivity are not critical to the patterning process.

A PhD candidate requested the following:

I am using these silicon wafers in a two-step photolithography process. I do not believe the dopant or resistivity will affect the process, but any dopant suggestions would be helpful.

Requested: 4 inch P-type <100>, 500 µm, SSP silicon wafers.

UniversityWafer Quoted:

Silicon Item #452 — 100 mm P-type <100>, 0–100 Ω·cm, SSP, 500 µm.

Reference #102246 for specs and pricing.

Get Your Photolithography Wafer Quote FAST! Or, Buy Online and Start Researching Today!





Quartz Wafers for Photolithography and Etching

Single crystal quartz wafers are used in photolithography, SAW devices, frequency control research, thin-film processing, and precision etching. Quartz provides excellent thermal stability, optical transparency, and chemical resistance for specialized microfabrication applications.

A research scientist requested quartz wafers for a photolithography etching project:

We have a new project studying the best temperature coefficient for small SMD TF devices. We will use a photolithography process to etch quartz wafers. The wafer size is flexible because budget is important. The required thickness is 0.1 mm and DSP.

UniversityWafer Quoted:

Item #U01-130301-2
25.4 mm Z-cut ±2°, 0.10 mm thick, DSP, SAW grade, seedless single crystal quartz.

Seedless single crystal quartz wafers for photolithography and etching

Reference #147879 for specs and pricing.

Through-Etch Photolithography Process

Through-etch photolithography is used to create openings, gas channels, microfluidic structures, membranes, and MEMS features through silicon wafers. Wafer thickness, orientation, dopant type, polishing, and masking layers should be selected based on the etch chemistry and final device geometry.

A mechanical engineering graduate student requested help selecting wafers for a through-etch process:

This is my first time ordering wafers. I would like to do a photolithography process with a wafer, more specifically a through-etch process. I think approximately 500 µm thick wafers would be good. I need 4 inch diameter undoped silicon wafers. The final structure will be used as a gas channel.

Reference #199865 for specs and pricing.

Photolithography Wafer Selection Help

If you are unsure which wafer is best for your photolithography process, send us your required substrate material, diameter, thickness, orientation, polish, resistivity, coating, oxide thickness, etch process, and quantity. UniversityWafer can help recommend silicon, quartz, glass, fused silica, sapphire, oxide-coated, or nitride-coated wafers for your research.

Copper-Coated Silicon Wafers for Photolithography

A postdoctoral researcher requested the following substrate for a heat transfer research project.

We are looking for a 3-inch copper-coated wafer with a thickness of 1–2 mm for a heat transfer experiment. The substrate will undergo a photolithography process, so the copper surface must be extremely flat and smooth. We anticipate requiring 5–10 pieces and would appreciate any recommendations if a standard product is unavailable.

Reference #139968 for specifications and pricing.

What Is the Photolithography Process?

Photolithography is the primary pattern transfer technique used in semiconductor manufacturing, MEMS fabrication, microfluidics, photonics, and nanotechnology. The process transfers microscopic patterns from a photoresist onto a substrate such as silicon wafers, glass, fused silica, or sapphire.

Photolithography process flow showing wafer cleaning, photoresist coating, exposure, development and etching

Typical Photolithography Process Steps

  1. Wafer Cleaning – Remove particles and organic contaminants before processing.
  2. Surface Preparation – Apply adhesion promoters such as HMDS to improve photoresist bonding.
  3. Photoresist Spin Coating – Deposit a uniform resist layer with controlled thickness.
  4. Soft Bake – Remove residual solvents while improving photoresist adhesion.
  5. Mask Alignment – Precisely align the photomask to the wafer using a mask aligner.
  6. UV Exposure – Transfer the circuit or device pattern onto the photoresist using ultraviolet light.
  7. Development – Remove either exposed or unexposed resist depending on whether a positive or negative resist is used.
  8. Etching or Ion Implantation – Transfer the developed pattern into the underlying material using wet etching, DRIE, plasma etching, or ion implantation.
  9. Photoresist Removal – Strip the remaining resist to expose the finished microstructures.

Positive vs. Negative Photoresist

The type of photoresist selected depends on the application.

  • Positive photoresist dissolves where exposed to UV light and provides excellent resolution for integrated circuits.
  • Negative photoresist hardens where exposed and is commonly used for thick structures such as SU-8 microfluidic molds and MEMS devices.

Common Substrates Used for Photolithography

The choice of substrate depends on the desired electrical, optical, mechanical, and thermal properties.

  • Silicon wafers — Standard substrate for semiconductor devices.
  • Thermal oxide silicon — Excellent electrical insulation and masking layer.
  • Fused silica — UV-transparent material for optical devices.
  • Glass substrates — Used for microfluidics and optical applications.
  • Sapphire — High-temperature optical substrate.
  • Quartz — Excellent dimensional stability and UV transmission.

Applications of Photolithography

Photolithography Equipment Required

A university laboratory requested assistance sourcing equipment needed to establish a complete semiconductor fabrication laboratory.

The laboratory required:

  • Tube furnace for thermal oxidation and annealing.
  • Spin coater for photoresist deposition.
  • Mask aligner for UV exposure.
  • PVD and CVD deposition systems.
  • Wet benches for chemical processing.
  • Wire bonder for integrated circuit packaging.
  • Wafer handling tools and vacuum wands.
  • Microscopes and inspection equipment.
  • Packaging materials and encapsulation resins.

The goal was to establish a complete educational cleanroom capable of fabricating integrated circuits from wafer preparation through device packaging.

Reference #316902 for specifications and pricing.

Need Photolithography Wafers?

UniversityWafer supplies silicon wafers, thermal oxide wafers, silicon nitride wafers, glass substrates, fused silica, quartz, and sapphire wafers for photolithography, MEMS, CMOS, semiconductor manufacturing, and research applications. Custom diameters, coatings, oxide layers, orientations, and wafer grades are available upon request.

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