Wafer dicing is a precision process used in semiconductor manufacturing to cut individual chips or die from a wafer.
Understanding Wafer Dicing
The wafer dicing process, also known as wafer sawing, wafer cutting, or die singulation, is a crucial step in the production of semiconductor devices. As stated in the reference, it is:
a precision process where semiconductor wafers are cut into small square or rectangular “chips” or “die” that are critical for the quality of all remaining post-fab processes and end-use performances.
This process takes a completed silicon wafer, which contains hundreds or thousands of identical integrated circuits (ICs) arranged in a grid, and separates them into individual units.
Key Aspects of Wafer Dicing
- Purpose: To singulate, or separate, the individual chips (die) that are patterned on the wafer.
- Input: A semiconductor wafer containing multiple identical or different integrated circuits.
- Output: Individual semiconductor chips (die) ready for packaging and assembly.
- Importance: The quality and precision of the dicing process significantly impact the integrity of the individual chips and the yield of good die. Poor dicing can cause physical damage to the chips, rendering them unusable.
- Methods: Common methods include mechanical sawing (using a diamond blade) and laser dicing.
Process Overview
The basic flow of the wafer dicing process involves:
- Wafer Mounting: The wafer is typically mounted onto a special dicing tape affixed to a frame. This tape holds the individual die in place after cutting.
- Alignment: The dicing equipment aligns itself precisely with the streets (the spaces between the die) on the wafer.
- Cutting: The dicing method (sawing or laser) moves along the streets, cutting through the wafer and the dicing tape.
- Cleaning: After cutting, the wafer and frame are cleaned to remove debris generated during the process.
- Picking: The individual die are then picked from the dicing tape using automated equipment and transferred for further processing (e.g., packaging).
| Stage | Description |
|---|---|
| Mounting | Attaching the wafer to tape and frame. |
| Alignment | Precisely locating the cutting paths (streets). |
| Cutting/Dicing | Separating the wafer into individual die. |
| Cleaning | Removing residue from the cutting process. |
| Picking (Die Sort) | Separating good die from the tape for assembly. |
In summary, wafer dicing is the essential step that transforms a large wafer containing many identical circuits into individual, usable semiconductor chips that can then be assembled into electronic devices.
