Tool for imaging and device modification

Description:

Focused ion beam (FIB)-based systems provide a versatile tool for performing work at the nanoscale. They can be used to selectively remove material from substrates and to direct write insulator and metal patterns while providing a high resolution inspection system, comparable to that achieved in the scanning electron microscope. These features have made FIB instruments a staple in failure analysis labs and semiconductor foundries alike.

CNF has recently installed a Hitachi FB-2000A to replace an old FEI 611 FIB system. Similar to the FEI, this tool uses a high brightness Ga liquid metal ion source coupled with a double lens focusing system to produce an intense beam of ions capable of being focused to a 40 nm diameter spot. It is capable of milling a variety of metals, semiconductors and insulators as well as depositing tungsten. The system is equipped with a vacuum load lock to enable rapid transfer of samples up to 3" in diameter.

Results:

Example of a cross section performed in the FEI 611 at CNF. In these micrographs, a multilayer interconnect structure was cross sectioned using the FIB. Following inspection in the FIB, the sample was removed and imaged in the Hitachi S4700. This underscores the usefulness of the FEI 611 in preparing cross-sectional samples for electron microscopy.