Structural modifications in ion-implanted silicate glasses

The structural modifications induced in fused silica and soda-lime glasses by implantation (argon, nitrogen! have been studied using step-height profilometry, Rutherford backscattering spectrometry, transmission electron microscopy, and scanning electron microscopy. The step-height measurements indicated a transformation in structure (-Delta L to +Delta L) at energy depositions on the order of 10(23) keV/cm(3) for both fused silica and soda-lime glasses. This change modifies the three-membered ring structure in fused silica initiated by the lower deposition energy of 1-2 x 10(20) keV/cm(3). The Rutherford backscattering spectrometry measurements show the initiation of the new structure by changes in the argon peak and a spreading of the argon to greater depths. The scanning and transmission electron microscopy measurements are complementary to these changes. The data presented can be understood in terms of ion-implantation induced stress.