Chemical Etching Technology for Polyimide Film and the Solution TPE3000
Features
- Polyimide film can be processed for blind-via or through-hole formation by chemical etching.
- TPE3000, which is used as a key chemical of the unique technology, is non-hydrazine type solution of alkaline nature.
- The solution can process various kinds of polyimide films and 2-layer films available in the market (Kapton, Apical, Upilex, Espanex, etc.).
- Both DFR (Dry Film Resist) and copper mask can be used as its etching mask.
- The chemical etching technology with TPE3000 assures overall cost reduction and higher productivity than with conventional mechanical processing technologies.
Specifications
| Object Material | Polyimide, 2-layer materials (cast, sputtered) |
|---|---|
| Side Wall Angle | Cu mask: 55-65 deg. |
| DFR: 40-45 deg. | |
| Etching Rate | (Fig.-1) |
| Operating Temperature | 60-90 °C |
| Appearance | Transparent and colorless liquid |
| Specific Density | 1.273 (25 °C) |
| PH | About PH13 (when diluted 100 times) |
| Regulation | Poisonous and Deleterious Substances Control Law, Deleterious Substance (IMDG8, IATA8) |
| Waste Chemical Processing | Vendor pickup |
Etching Performance（Fig.-1）
Example of mixed processes (Flying-lead, Blind via-holes, Through-holes)
Flying-lead
Blind-via
"Through-hole for liquid crystal polymer"
At present, liquid crystal polymers are commercially available from a number of companies.
Some polyimide substrates may be replaced with liquid crystal polymers, but we have developed etching solutions for liquid crystal polymers as a new series of the polyimide etching solution "TPE3000".
The photo shows an example of processing with a liquid crystal polymer thickness = 125µｍ and a bottom diameter = 400µｍ.
