Kovar Etchants

Kovar is a nickel-iron-cobalt alloy known for its low coefficient of thermal expansion, making it ideal for use in electronics and telecommunications applications. Chemical etching of Kovar is a process used to create precise patterns, markings, or designs on Kovar surfaces, often for the manufacturing of components like hermetic seals, electronic packages, and connectors. Here’s a guide on commonly used methods for etching Kovar and how to set important parameters for effective Kovar etching:

Commonly Used Kovar Etchants

  1. Ferric Chloride (FeCl3)


  • Electronic Packaging: Kovar is commonly used for electronic packages, and etching can be employed for quality control, surface treatment, and marking.
  • Hermetic Seals: Kovar is used in hermetic seals for electronic and telecommunications components. Etching may be used for shaping these seals.

Setting Parameters:

  • Temperature: Kovar etching with ferric chloride is typically performed at temperatures ranging from 35°C to 45°C (95°F to 113°F).
  • Concentration: A common concentration is around 40-45% ferric chloride in water. Ensure thorough mixing for consistent results.
  • Etching Time: The etching time can vary based on the desired result and the thickness of the Kovar, ranging from minutes to several minutes.
  • Agitation: Utilize an agitation mechanism within the etching equipment to maintain even etching and prevent the accumulation of byproducts.

Setting Parameters in a Kovar Etching Operation

For an effective Kovar etching operation using ferric chloride as an example:


  • Confirm and set the etching machine’s temperature control settings within the specified range of 35°C to 45°C.


  • Measure the required amount of ferric chloride accurately and mix it with water to achieve the desired concentration (e.g., 40-45%). Use calibrated instruments for precision.

Etching Time:

  • Determine the appropriate etching time based on the thickness of the Kovar and the complexity of the design. Start with a short duration and adjust as needed. Typically, a 10-15 minute initial test run is a good starting point.


  • Ensure that the etching equipment is equipped with an agitation system to maintain proper mixing of the ferric chloride solution throughout the etching process.


  • Prioritize safety when working with ferric chloride. Always wear appropriate personal protective equipment (PPE) such as gloves, safety goggles, and lab coats. Maintain a well-ventilated workspace with safety showers and eyewash stations.

Waste Disposal:

  • Dispose of used etchant solutions following local regulations, as ferric chloride waste is often considered hazardous. Proper handling and disposal are essential.

If you have an Kovar etching project that you need help with, please contact us