  Bond pads are the electrical interconnections of a microelectronic device to
the outside world. A polyimide layer (PI) on top of a microelectronic device
protects the whole device against environmental impacts. The bond pads are
accessible though openings in this electrically insulating layer. The oxide
layer thickness and contaminations at the Al bond pad surface influence as well
the quality of the mechanical and electrical joint between bond pad and bond
wire as the durability of this interconnection. If a bond pad surface has to be
analyzed with high spatial resolution Auger electron spectroscopy (AES) is the
method of choice. AES utilizes an electron beam for excitation, which induces
serious sample charging because of the PI layer. Sample charging can be avoided
by metal grids, which are common in transmission electron microscopy (TEM)
sample preparation. A TEM grid is pressed onto the sample while the bond pad of
interest is centered in the square openings of the grid. Exemplarily analyses
of bond pads demonstrate the applicability of this approach for AES
measurements.
