Wafer foundries provide process services that turn a bare substrate into a structured, coated, etched, bonded, thinned, or tested wafer. The service scope depends on the foundry’s equipment, material compatibility, wafer size range, inspection capability, and engineering support. For many projects, the value of custom wafer foundry services is not only processing one step, but connecting multiple steps into a controllable route.

Plutosemi’s wafer foundry page lists these service groups and states compatibility with 4 inch, 6 inch, and 8 inch wafer lithography, while coating and etching equipment are compatible with wafers up to 8 inches.

Lithography Services

Lithography defines the pattern that later process steps will follow. It can be used for MEMS structures, microfluidic channels, optical patterns, sensor electrodes, interconnect layouts, and research test structures. Plutosemi lists double-sided UV lithography, DUV lithography, stepping lithography, glue development equipment, cleaning equipment, and HMDS ovens as part of its lithography support.

For projects involving wafer lithography etching bonding, lithography must be coordinated with downstream etching and bonding requirements. Alignment tolerance, resist thickness, exposure method, and pattern size all affect the final result.

Coating And Film Deposition

Coating services form metal, dielectric, or functional layers on the wafer surface. Plutosemi lists PECVD, LPCVD, ICPCVD, ALD, multi-chamber magnetron sputtering, and electron beam evaporation stations. Available materials include Ti, Al, Cu, Au, Cr, Pt, Ag, Mo, W, TiW, AuGe, poly-Si, amorphous silicon, SiO₂, SiNx, TEOS SiO₂, ITO, Al₂O₃, TiO₂, TiN, and AlN.

Film selection should follow the device target. Metal films may be used for electrodes or seed layers. Dielectric films may support insulation, passivation, or optical control. Functional films may be selected for sensors, RF devices, or optical components.

Etching And Pattern Transfer

Etching removes selected materials according to the lithography pattern. Plutosemi lists RIE, ICP, IBE, and wet etching equipment, with etching material support for Si, SiO₂, SiNx, amorphous silicon, polysilicon, Au, Al, Cr, Ti, W, GaN, and ITO.

Etching requirements should include target depth, profile, sidewall requirement, material stack, mask type, and allowed surface damage. For MEMS or micro-nano structures, small changes in etch uniformity may affect function.

Bonding, Thinning, Cutting, And Packaging Support

Wafer bonding and thinning are important for MEMS, sensors, 3D integration, interposers, and advanced packaging structures. Plutosemi lists CMP, bonding alignment machines, wafer temporary bonding, wafer permanent bonding, high-pressure wafer bonding, Silicon Wafer cutting, bonding, cutting, and thinning equipment compatible with 6 inch and 8 inch wafers.

These steps require careful geometry control. TTV, bow, warp, surface roughness, cleanliness, and bonding layer condition should be checked before bonding starts. Poor incoming substrate quality can cause voids, misalignment, breakage, or thickness variation.

How One Stop Processing Helps

A one stop wafer processing route can reduce handoff risk. When lithography, coating, etching, bonding, cutting, and testing are coordinated by one technical team, process feedback becomes easier. Measurement results can guide the next adjustment, and drawing changes can be communicated without restarting the entire supplier review process.

Plutosemi also supports TGV and TSV process services. TGV is described as a vertical electrical interconnect through glass substrate, while TSV is described as vertical electrical interconnection through silicon channels for 2.5D and 3D packaging. These services show that wafer processing may extend from surface patterning into advanced interconnect structures.

Summary

Wafer foundries provide lithography, coating, etching, implantation, bonding, thinning, cutting, testing, and process development support. The right service plan should be based on wafer material, drawing, film stack, critical dimensions, inspection needs, and final device function. Plutosemi can support customized wafer foundry programs by combining material supply, micro-nano processing, packaging-related steps, and inspection capability.