Phoenix® Edge Pad Conditioners
New materials being developed are improving the CMP conditioning step and improving yield and productivity in the chip fabrication process.
MTC Diamonex’s novel enhancement to the material is the development of Phoenix® Edge pad conditioners. Contact is made by the edges of a precisely-machined proprietary ceramic substrate with elevated surface features coated with a CVD diamond film.
This diamond surface has the advantage of multiple cutting facets compared with only one or two cutting edges of a single diamond crystal particle. The edges of the novel material, that can be designed in a variety of patterns including spirals or concentric circles with specifically-engineered dimensions, produce pad textures that optimize CMP performance for each application.
Characteristics
• A smoother pad texture with fewer large asperities
• Asperity shapes with a sharpness in the mid range of point cutting (traditional gritted conditioners); however, for point-cutting the number of sharp asperities decreases with diamond size
• Smaller, elongated curled contact area shapes as opposed to larger round contact regions for point-cutting
• Less contact area, fewer number of contact points, and fewer large contact regions
Performance
Test results in a Copper study on blanket wafers
• Approximately 40% increase in copper removal rate over point cutting
• Vastly reduced pad cut rate over point cutting
• Improved planarity
• Lower Pad RA
Summary
The edge conditioners produce a lower pad cut rate (extends the life of the pad), a smoother surface (less defects), improved material removal rate from the wafer and improved planarity.
