Potassium hydroxide-KOH etching is an efficient chemical process that allows for precise impressions to be made within a body of silicon. The process uses DI (deionized) water in combination with heavy alkalinity (pH levels greater than 12); the solution is then thermally adjusted for the appropriate degree of etching needed. This process allows for greater precision than other forms of etching when it comes to manufacturing silicon wafers.
What Are the Benefits of Using KOH Etching?
The precision KOH etching grants is very beneficial to the product’s outcome. Due to its chemical composure and procedural approach, dry etching is more apt to create physical flaws; it also can make for a more hazardous environment, as it risks the exposure of toxic — even explosive — chemicals.
KOH etching, on the other hand, is almost entirely aquatic. The liquids for the etching process are contained within Modutek’s own Teflon Tanks, meaning that exposure to hazardous chemicals is drastically reduced to create a safe environment for manufacturing. The structuring behind the process also means that it can easily be set up for repeat manufacturing; the resources required for the etching are more stable and affordable, meaning that clients can duplicate their etchings at a much more feasible rate.
How Do Teflon Tanks Bolster the KOH Etching Process?
Modutek’s Teflon Tanks are designed with the foresight to emphasize the maximum potential KOH etching can provide. Furthermore, each Teflon Tank is fashioned to cater to the specific needs of the client, regardless of unorthodoxy. In unison with wet bench equipment, these Teflon Tanks greatly reduce the impurities other methods of etching may establish, providing you with a more reliable and consistent output every time.
The Teflon Tanks can be thermally adjusted to operate between 30 — 100º C (86 — 212º F), and on average can heat up at a rate of 2 — 3º C per minute, though smaller or larger tanks may have varying thermal increase rates. Thermal output can be mustered either from inline Teflon heating, or from submersion within an overflow bank for each type of Teflon Tank. Each tank is also fitted with cooling coils that can quickly reduce the solution’s temperature.
There are two types of Teflon Tanks that support KOH etching: Temperature Controlled Re-circulating Baths (TFa Series), and Temperature Controlled Static Baths (TI Series). These two series of Teflon Tanks are designed with overlapping covers to minimize the loss of water during the etching process; they also boast the ability to eliminate concentration deficiency.
Because Modutek designs their Teflon Tanks with the client’s specifications in mind, the customization each tank receives is advantageous to the desired end result. Dual heating methods produce a quick, balanced aid to water-based etching. Drains and valves can be installed into the tanks for safe and easy clean-up. Remote timers, controllers, or even a data interface can be equipped to make a simple process even simpler.
When compared to other forms of etching (whether wet or dry), Modutek’s support of KOH etching produces more precise and affordable results in a safer and more expeditious work environment. Teflon Tanks can be produced individually or en masse depending on the output the client is in need of. Each tank can also be fitted with a number of practical options that can improve the etching process dramatically.
No client should work with an environment or product that diminishes the quality of their manufacturing process; customization leads the way for an innovative and effective product. Modutek’s support of KOH etching in their catalytic Teflon Tanks will provide exceptional results for clients that use this process.
