-Chemical etching is the process of removing material from a surface through exposure to an agent.
-Chemical etching is used in various industries but especially effective in food industry, medical instrumentation and research fields. The major advantage of chemical etching is that it can create intricate designs or patterns with precise sizing. Moreover the chemicals used are non-toxic and environmental friendly unlike other techniques such as laser cutting or photochemical machining which emits harmful chemicals into air and creates toxic byproduct wastes.
-The first step for this process includes preparing a specific masking material on top of an electrolytic copper plated substrate. This application method enables the selective deposition of any kind of metal over insulating base materials like glass, ceramic and plastics. Next step includes exposing the metal to a chemical agent which dissolves only the exposed area.
-The masking material can be either organic or inorganic compounds. In case of organic compounds, the etching process may include acids, alkaline solution and plasmas whereas, with an inorganic compound it involves halogens or halogenated compounds such as hydrofluoric acid (HF), KOH and TMAH.
-Chemical etching is used for pattern transfer from photomasks to substrates and microstructures photo resist development and defect repair. Etchants vary considerably depending on their application:
-When this process was first invented it included wet chemical processing however currently most of them use plasmachings as it is more effective and economic.
–Chemical etching is used to produce microstructures in silicon wafers, patterns on semiconductor components and metal films for printed circuit boards or integrated circuits. It can be performed either using a wet process or a dry process:
-This process mainly includes the chemical reaction between acids and elements such as aluminum, chromium and nickel which helps to reduce the thickness of the metals layer over tall structures leaving behind tall vertical walls that can support heavy loads making it especially effective in research fields such as biomedical engineering where surgical blades require high durability with minimal weight. This also enables designer engineers to create lighter products such as aircraft parts with higher strength than other existing methods such as injection molding could provide.
-In medical applications this technique is used to make micro-injection mold, micro tools for surgery and biological implants. In aerospace industry it is needed to create molds for lighter aircraft parts. In the food industry it is used for making holes in cap of bottles without causing any damage to the underlying material.
-Chemical etching method has a few disadvantages such as the dependence on chemicals and their contact with humans can also cause chemical burns, corrosion and need high temperature cleaning after use. In research field this process requires more time than other conventional methods such as wet etching. Moreover, when fabricating semiconductor devices, quality may depend on contaminants that will result in contamination or defects in the finished product if not properly handled during manufacturing process.
-Chemical-etching services are available at companies such as MikroTools Inc which provide custom micro fabricated parts using this technique.
Conclusion:
–Chemical etching is an advanced technique used to create patterns on various materials for different purposes. It does not damage the surface of the materials like other machining methods and can be performed with non-toxic chemicals thus environmental friendly. Although, it requires high temperature that may not be suitable for all kinds of substrate materials therefore material selection should be done before using this process.