Silicon Nitride Deposition (SiN)

Inductively Coupled Plasma Chemical Vapour Deposition SiN

• Uniformity   ± 2 - 4  % over one full batch
• Deposition rate 10 - 15 nm/min, max 100 nm/ min
• Refractive Index typically 2.0, but fully controllable 1.8 - 2.5

Ionfab 300Plus

Process Specification
Si3N4 RIBD in the Ionfab300Plus (LC)

• Pre-clean: 35cm source can pre-clean up to 200mm substrates
• Deposition Gases: Ar, N2
• Up to 200mm wafers
• Summary performance data:

a. After 12 hours bake out at 80°C.
b. Load lock pumps down to 6E-5Torr in less than three minutes. It takes less than five minutes from sample loading i.e. from the load lock to process platen with load lock pump down sequence.

Process specification

1. Si3N4 deposition with rotation and adjustable tilt.

1. With 5mm edge exclusion
2. Stress and uniformity value are guaranteed for deposition rates up to 50% of maximum rate

Additional Notes:

1. The data given above applies to High Frequency films. 
2. Accuracy of measurement of low stress values is highly dependent on:

• the accuracy of wafer curvature measurement both before and after film deposition
• the quality and pre-stressing of wafers used for stress measurements
• and requires a thick film (>5000Å) to produce a detectable/accurately measurable wafer curvature

3. Results given above apply to Silicon substrates.
4. Cleaning and conditioning of the chamber may be required when switching between processes, to obtain optimum repeatability. A minimum conditioning thickness of 2000-3000A is recommended. Further advice on chamber cleaning/conditioning strategies will be provided by OIPT based on customers’ applications and intended use of system.
5. Standard definitions of uniformity given below:

Within wafer uniformity is measured in a five point pattern:		Run-to-run uniformity (reproducibility) is calculated from average wafer uniformity in 5 consecutive runs.
		For refractive index uniformity is calculated as:       For refractive index uniformity is calculated as: