Indium surface undergoing laser cleaning showing precise contamination removal

Indium Laser Cleaning

Precision laser cleaning safeguards Indium's soft, low-melt integrity

Ikmanda Roswati
Ikmanda RoswatiPh.D.
Ultrafast Laser Physics and Material Interactions
Indonesia

Properties: Indium vs. other metals

Laser-Material Interaction

Material Characteristics

Other Properties

Machine Settings: Indium vs. other metals

Indium surface magnification

Laser cleaning parameters for Indium

Before Treatment

Under microscopy, the indium surface appears very-very contaminated with fine dust particles and oily residues that cling tightly and spread unevenly. These contaminants cause degradation, so pits and scratches form, making the metal look rough and dull.

After Treatment

The cleaned Indium surface restores very-very smoothly and appears pristine. Material integrity remains intact, so quality is high.

Indium Laser Cleaning FAQs

Can I safely remove indium oxide from components using a laser cleaner without damaging the underlying pure indium?
Ya, pembersihan laser dapat menghilangkan oksida indium dengan aman. Gunakan parameter terkontrol seperti fluence ~2.8 J/cm² dan spot 80 µm untuk mengablasikan lapisan oksida tanpa melelehkan substrat indium murni di bawahnya. Pembersihan ini efektif karena perbedaan ambang ablasi antara oksida dan logam dasarnya.
What are the specific laser parameters (wavelength, power, pulse duration) recommended for cleaning indium-tin oxide (ITO) coatings from glass substrates?
Untuk membersihkan ITO dari substrat kaca, gunakan laser 1064 nm dengan fluens ~2.8 J/cm² dan durasi pulsa nanodetik. Parameter ini mengablasikan lapisan oksida secara terkendali tanpa merusak kaca di bawahnya, mengoptimalkan daya 45 W dan kecepatan pemindaian 500 mm/s untuk hasil yang bersih dan presisi.
Is laser cleaning effective for de-oxidizing indium solder pads or pre-treatment for re-soldering, and does it leave a residue?
Laser cleaning effectively removes indium oxide at 2.8 J/cm² fluence without residue, significantly improving solderability. This non-contact method outperforms chemical alternatives by eliminating redeposition and preserving the pristine surface quality essential for reliable re-soldering.
What specific fume extraction and filtration requirements are needed when laser cleaning indium due to its toxicity?
Laser cleaning indium requires HEPA/ULPA filtration due to highly toxic oxide fumes. With a fluence threshold of 2.8 J/cm², continuous air monitoring for indium compounds is essential. Operators must use supplied-air respirators to prevent pulmonary exposure.
How does indium's low melting point (156.6°C) affect the laser cleaning process and what are the risks of surface smearing or damage?
Indium's 156.6°C melting point demands exceptional thermal control. We use nanosecond pulses at ~2.8 J/cm² to ablate oxides, but exceeding this fluence risks surface smearing. Successful cleaning leaves a uniform metallic sheen, while damage appears as a dull, re-solidified layer.
Can a fiber laser be used to clean indium, or is a different laser type (like Nd:YAG) required for better absorption and control?
Fiber lasers at 1064 nm wavelength can effectively clean indium, achieving oxide ablation at ~2.8 J/cm² fluence. While Nd:YAG systems offer excellent control, modern fiber lasers provide sufficient absorption and precision for most industrial applications, such as electronics manufacturing.
What is the best method to verify the surface cleanliness and purity of indium after laser cleaning, especially for high-vacuum or semiconductor applications?
For high-vacuum indium surfaces cleaned at ~2.8 J/cm², XPS is essential to verify sub-monolayer oxygen removal. Complement this with contact angle measurement; a significant increase confirms the desired hydrophobic, oxide-free surface required for semiconductor bonding.
Are there any risks of generating electrically conductive nanoparticles when laser cleaning indium or ITO, and how can they be mitigated?
Laser cleaning indium at 2.8 J/cm² fluence can generate conductive nanoparticles. We mitigate this risk by using an argon shielding gas and optimizing the 500 mm/s scan speed to prevent redeposition, ensuring no short circuits on sensitive electronics.
How does laser cleaning performance on indium compare to traditional methods like chemical etching or mechanical abrasion for precision components?
Laser cleaning offers superior precision for indium components, operating effectively at 2.8 J/cm² to remove oxides without chemicals. However, its thermal risk requires careful control to avoid melting the low-melting-point metal. This makes it ideal for delicate electronics but less suitable for high-volume, cost-sensitive applications where traditional methods suffice.
What are the primary industrial applications where laser cleaning of indium is most commonly required?
Laser cleaning of indium is essential in semiconductor manufacturing for cryogenic sealing surfaces and in display production for ITO repair. Using a 1064 nm wavelength at ~2.8 J/cm² fluence effectively ablates the oxide layer without damaging the soft underlying metal, ensuring optimal electrical contact and bond integrity.

Regulatory Standards & Compliance