Physical vapor deposition (PVD) forms a thin film by transferring material from a source to a substrate in a vacuum process. In semiconductor manufacturing, start with the film's function and the features it must cover. Then choose the process and measurements needed to establish that the deposited layer meets those requirements.
Understand the source of the deposited material
Two major PVD approaches are evaporation and sputtering. Evaporation heats source material so it enters the vapor phase. Sputtering ejects material from a target through energetic particle bombardment. Equipment geometry and process conditions affect how that material reaches the substrate.
Kurt J. Lesker's deposition overview explains thermal and electron-beam evaporation and the role of combined deposition systems. Its material deposition chart helps identify candidate methods for specific materials. These references support an initial process discussion; a qualified recipe depends on the actual stack, tool and required film.
Document the substrate surface condition, permitted thermal exposure and any underlying layers that the process could affect. Include target or source identity and chamber condition in the record. When layers are deposited sequentially, define which interfaces require controlled transfer and how cross-contamination is addressed.
Translate film function into evidence
On a narrow screen, scroll the table horizontally. Keyboard users can focus it and use the arrow keys.
| Requirement | Possible evidence | Scope to define |
|---|---|---|
| Thickness and distribution | Calibrated thickness map | Sites, edge exclusion, model and uncertainty |
| Electrical behavior | Sheet-resistance or device test | Film continuity, substrate and test geometry |
| Interface integrity | Applicable adhesion/reliability evaluation | Complete stack and subsequent processing |
| Feature coverage | Representative cross-section or other validated measurement | Top, sidewall and bottom of relevant features |
KLA's metal-film mapping note discusses four-point-probe and eddy-current approaches to sheet resistance and thickness. Electrical and thickness results have different dependencies; retain the method and material assumptions used to interpret either.
Choose measurements for the intended decision. A blanket witness can track a process under a defined correlation, while patterned product features need representative evidence for their geometry. Record the substrate and location of every witness so its relevance can be assessed.
Define uniformity before comparing percentages
Fictional five-site map: thicknesses are 98, 100, 102, 99 and 101 nm. Their mean is 100 nm. Define uniformity here as (maximum − minimum) ÷ (2 × mean) × 100%. The result is (102 − 98) ÷ 200 × 100% = 2%.
Using the full range divided by the mean gives 4% for the same data. Both calculations can be reported accurately only with their definitions. Save the coordinates and values alongside the summary.
Five measured sites leave the unmeasured area unresolved. Expand the sampling plan as required by the process risk and observed distribution; keep edge exclusion consistent between comparisons.
Qualify repeated films and relevant features
Plan representative runs across wafer positions and the chamber conditions included in the release. Keep thickness, composition where required, electrical behavior, adhesion and feature coverage as separate acceptance items. Investigate one failed property without assuming all other properties moved with it.
Link a process change to its affected requirements. A new target, chamber clean, geometry or substrate preparation can trigger a defined requalification review. Retain the baseline and approved recipe revision so the trial can be reconstructed.
The lithography guide explains the patterning context, while parametric testing covers electrical characterization. The finished process record should show what the film evidence establishes for the intended device, with open questions assigned to an owner.
Use the working record
Download the editable pvd film qualification. Save a copy, complete the actual requirements and evidence fields, and review open issues with the responsible owner. The plain-text record includes instructions, units where needed, the fictional example, and source references.