1. What is Wafer Yield?

Wafer yield is a critical metric in semiconductor manufacturing that measures the percentage of functional dies (chips) on a silicon wafer compared to the total number of dies. It indicates the efficiency and quality of the manufacturing process.

2. How Does the Calculator Work?

The calculator uses the yield formula:

Where:

• Good Dies — Number of functional, non-defective dies on the wafer
• Total Dies — Total number of dies on the wafer (functional and defective)

Explanation: The formula calculates the percentage of good dies relative to the total number of dies on the wafer, providing a measure of manufacturing efficiency.

3. Importance of Yield Calculation

Details: Yield calculation is essential for semiconductor manufacturers to assess process efficiency, identify production issues, calculate production costs, and improve manufacturing quality. Higher yields mean lower production costs per functional chip.

4. Using the Calculator

Tips: Enter the number of good dies and total dies as whole numbers. Good dies cannot exceed total dies, and total dies must be greater than zero.

5. Frequently Asked Questions (FAQ)

Q1: What is considered a good yield in semiconductor manufacturing?
A: Yield expectations vary by technology node and product type, but modern fabs typically achieve yields of 90-99% for mature processes.

Q2: What factors affect wafer yield?
A: Yield is affected by process variations, contamination, defects, mask errors, equipment performance, and environmental conditions in the cleanroom.

Q3: How is yield different from defect density?
A: Yield measures the percentage of good dies, while defect density measures the number of defects per unit area. They are related but distinct metrics.

Q4: Can yield exceed 100%?
A: No, yield is a percentage that cannot exceed 100% as good dies cannot outnumber total dies.

Q5: Why is yield important for cost calculation?
A: Manufacturing cost per functional chip is inversely proportional to yield. Higher yields mean lower costs as the fixed wafer cost is spread across more good chips.