BEHAVIOR OF AR AT THE SURFACE AND BONDED INTERFACE OF COPPER TREATED BY AR ION-BOMBARDMENT

Ion bombardment is known to be effective in removing all surface conta minations and oxides and improving the quality of diffusion bonds. How ever, recent work has shown that the accelerating voltage used during the ion bombardment significantly affected the bond strengths. This wo rk has been carried out to investigate the behavior of argon at the su rface and bonded interface of copper which are treated by the argon io n bombardment. To observe changes at the surface and the bonded interf ace, surface composition, surface morphology, gas analysis in voids at interface were investigated, using Auger spectroscopy, reflection hig h electron diffraction (RHEED), and mass spectrometer technique. Resul ts obtained are summarized as follows: 1. On argon ion bombardment, ar gon penetrates the surface of copper, and the amount of argon planted increases with accelerating voltage during ion bombardment. When the c opper surface is heat-treated, argon is released from the specimens, a nd the concentration of argon at the surface layer decreases. 2. Argon ion bombardment deteriorates surface flatness and crystal perfection. The extent of these damages increases with a rise of the accelerating voltage. 3. Argon comes out from the voids at bond line of joints mhi ch are made using specimens treated by the argon ion bombardment. The presence of argon in the voids is one reason for the deterioration of the joint in the samples bombarded at a high accelerating voltage. 4. The annealing of the samples after the ion bombardment makes the bondi ng surface clean, removes any surface damage and gives joints free fro m voids at the bond line. 5. The annealing treatment is effective in r emoving the surface damage introduced by the argon ion bombardment.