Chemical Etching Studies of Pure and Amino acids Doped KDP Crystals

Potassium dihydrogen phosphate (KDP) and amino acids are non-linear optical material used for laser frequency conversion. The pure and amino acids (L-arginine, L-lysine and L-alanine) doped KDP crystals were grown by slow solvent evaporation technique. The amino acid doping was confirmed by CHN analysis, paper chromatography and FTIR studies. The (100) face of pure and amino acids doped KDP crystals were selected for the chemical etching studies. The etchant used for all crystals were glacial acetic acid (CH3COOH). The etching temperature was varied from 25 C to 40 C with increment of 5 C. The etch pits was measured and Arrhenius law applied. The values of kinetic and thermodynamic parameters ware evaluated from width of etch pit.