Selecting the right Secondary Ion Mass Spectrometry (SIMS) provider is crucial for semiconductor manufacturers. Dynamic SIMS is an invaluable tool for quality control, failure analysis, and R&D. This guide helps you identify the key quantitative and qualitative metrics you should use to evaluate your SIMS providers.
Why Metrics Matter
With few vendors in the market and claims of similar service portfolios, SIMS vendor performance can vary widely. Quantitative metrics such as turnaround time and repeatability provide a baseline understanding of their capabilities. However, qualitative aspects like communication and data transparency are equally important for successful long-term partnerships.
The Impact of SIMS and SIMS Vendor Selection
SIMS is the most sensitive technique for measuring the chemical properties of semiconductor materials, making it an indispensable tool for R&D, quality control, and failure analysis in semiconductor manufacturing. Because SIMS can detect elements to the parts per trillion (PPT) level, it is often used for equipment qualification and as a gating technique for manufacturing statistical process control (SPC). This sensitivity, however, is only as useful as the bounds of certainty, making accuracy and precision indispensable metrics in the usefulness of SIMS data. Furthermore, when used as a gating technique, the reliability of a SIMS analysis provider becomes paramount to the bottom line of semiconductor fabrication organizations.
Key Takeaways
- Turnaround Time: Check if vendors track and publish how often they meet or exceed their promised deadlines.
- Repeatability & Precision: Evaluate short-term and long-term Relative Standard Deviation (RSD).
- Accuracy: Ask vendors if they can track and provide long-term accuracy metrics.
- Data Transparency: Choose vendors that share data processing methods openly. It may otherwise be difficult to switch vendors or have a backup vendor for business continuity.
- Access to Expertise: Select partners that offer direct access to scientific experts: interpreting SIMS data can sometimes require experts in both SIMS and semiconductor manufacturing.
Quantitative Metrics to Evaluate SIMS Vendors
Quantitative metrics offer an objective way to compare SIMS providers. These include:
Accuracy:
Does the provider track and report long-term accuracy? Consider vendors who offer continuous accuracy improvement programs. These metrics should be meaningful and are important to establish uncertainty budgets for statistical process control. A semiconductor-focused SIMS lab, for instance, may use integrated dose of reference material to gauge long-term accuracy uncertainty across equipment and configuration.
Repeatability & Precision
Review short-term and long-term precision metrics, typically provided as Relative Standard Deviation (RSD). Some vendors charge a fee for these metrics. Keep in mind even relatively small differences can compound, having large impacts on full-process and long-term statistical uncertainty.
Turnaround Time
Can the vendor consistently meet deadlines? Look for metrics that specify on-time delivery rates.
Detection Limits:
Verify that the vendor can meet the sensitivity requirements, particularly for important elements for semiconductor manufacturing, such as Boron or Phosphorus in implants, or contaminants like Carbon or Oxygen. Ask the vendor if they have continuous improvement programs that regularly look at potential updates to methods, equipment, and processes to ensure the best possible detection limits.
Qualitative Metrics for Vendor Evaluation
Quantitative metrics are not enough to make an informed decision. Consider these qualitative factors as well:
Data Transparency:
Does the provider share data processing methodologies openly? SIMS data requires significant processing to provide quantified data (depth and concentration). Lack of transparency in processing can lead to vendor lock-in and inability to develop a robust business continuity strategy for SIMS. Ensure vendors are open about their processing methods and provide both unprocessed and processed data to show data provenance.
Interaction & Communication:
How well does the vendor explain complex results and engage with your team? It is not uncommon for multiple roles and varying seniorities of colleagues to interact with the SIMS vendor. Ensure they have the communications competency to engage with a wide variety of individuals such as your most junior process engineer or a senior manager.
Access to Expertise:
Can you easily access experts for technical discussions? For most organizations, vendor-provided expertise at the intersection of SIMS and semiconductor manufacturing is required when considering a new type of analysis, interpreting results, identifying potential root causes, and planning long-term quality control.
Process & Operational Alignment:
Is the vendor’s service model compatible with your procurement, quality control, and technical processes? Ensure the vendor's purchasing, servicing, results reporting, and billing practices are compatible or can be customized by the vendor to align with your internal processes. Since SIMS data can often be time-critical, compare their processes for requesting analysis, confirming receipt of samples, tracking work-in-process, and delivering results.
Template Process for Vendor Evaluation
To effectively evaluate potential SIMS vendors, consider following this step-by-step process:
Initial Screening
Request key metrics from each vendor and verify accreditation (e.g., ISO/IEC 17025:2017).
Engage in Demonstration Analysis
Have the vendor conduct a small-scale analysis with a real sample and evaluate vendor interaction, data quality, and reporting comprehensiveness. Request a pre- and post-analysis expert review as a basic test of the communication and expert engagement processes the vendor has implemented.
Review Interaction Quality
Assess how well the vendor communicates results and whether they align with your processes. Ask the vendor what, if any, parts of their service processes are customizable.
Medium-Term Comparison
If you're using an existing provider and considering a new provider, consider splitting analyses between vendors for some period of time, comparing the service each provides.
Long-Term Tracking
Consider tracking the vendor's precision, accuracy, and turnaround time adherence, and regularly comparing against their stated or promised thresholds.
Why Beamline?
At Beamline, we’re more than just another SIMS lab. We focus exclusively on the semiconductor industry, offering:
- 99.9% on-time or faster analysis delivery, measured in calendar not business days, with night and weekend lab operations.
- Unmatched data transparency, existing vendor data processing matching, and access to scientific expertise before and after analysis.
- 30%+ lower costs compared to the leading vendor.
Choosing the right SIMS provider doesn’t have to be daunting. Contact us to talk to an expert or get a quote.