Selective Etching of Al x Ga1 − x As and In ( Al x Ga1 − x  ) As Alloys in Succinic Acid‐ Hydrogen Peroxide Solutions

Succinic acid‐hydrogen peroxide solutions were used to etch and alloys, and the etch rates were investigated with the varying alloy mole fractions. It was found that may be selectively etched over , with a selectivity better than 150. Extended surface exposure to air was found to affect the etch rates, most interestingly for . In the system, alloys with can be preferentially etched over with a selectivity of better than 20.