Method for Metallization Stripping of Gold Interconnected Semiconductors Using an Aqueous Potassium Iodide Solution

Extract

Thin films in microcircuits can vary from as little a few hundred angstroms, in the case of dielectrics such as silicon nitride and silicon dioxide, to several microns in the case of interconnects. However, most metallization systems used as interconnects and in active structures are generally in the order of 0.5 μm to 4 μm. Gold has a number of desirable properties such as high electrical conductivity, the ability to be easily electroplated, low residual stress after deposition, corrosion resistance etc., Gold is commonly found in microelectronic devices, particularly in high frequency applications like cellular telephony, fiber-optic amplifiers and other high frequency analog applications. An aqueous potassium iodide solution offers a fast and relatively safe method for the removal of thin gold films.