Why do sputtered windshield coatings sometimes appear clear in one area and cloudy o r streaky in another?

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Why do sputtered windshield coatings sometimes appear clear in one area and cloudy o r streaky in another?

This partial clarity often occurs in MS-HS deposition when there is an uneven plasma distribution, target wear, o r inconsistent substrate heating. How can Pakistani facilities monitor and correct these issues to achieve full-area uniform transparency on glass?

Talha Kyanii asked on 26 Jul 2025 16:10:25 pm

1 Answer

30 views |

Gari Master - on 26 Jul 2025 16:31:46 pm

This is usually due to:

Plasma density variation

Non-uniform target wear

Substrate not aligned properly

Localized overheating

Such issues are common in setups without proper maintenance o r diagnostics, especially in smaller facilities in Pakistan.

Preventive measures:

Calibrate plasma distribution using diagnostic tools e.g., Langmuir probes, visual arc tracking.

Replace o r rotate worn targets.

Keep substrate flat and centered in the chamber.

Avoid excessive heating during high-speed sputtering.

Q5: What role does deposition rate play in the formation of streaks on transparent films used for windshields in Pakistan?
Answer:
High deposition rates can cause:

Poor surface mobility of atoms

Low film density

Columnar growth o r rough morphology

Optical haze o r visible streaks

In Pakistan, where faster throughput is often prioritized, this leads to compromised film quality.

Suggestions:

Optimize for moderate sputtering rates—balance speed and film quality.

Maintain substrate heating ~100–150°C if the material allows, for better film structure.

Adjust working pressure and power levels to control film growth rate.