D & TOF‐SIMS failure analysis of P‐buried layer from BiCMOS transistors

Abstract

D & TOF-SIMS instruments are used in conjunction with other analytical techniques in order to identify the sources of metallic contamination and particle-type defects. In this paper D & ToF-SIMS are used to identify metals in the P-type buried layer of BiCMOS transistors and eliminate them in order to improve the overall device performance and process yield.

A-Crater-within-a-Crater Approach for Secondary Ion Mass Spectrometry Evaluation of the Quality of Interfaces of Multilayer Devices

“…Secondary ion mass spectrometry (SIMS) is a very precise analytical technique for determining the elemental composition of a sample − and is especially well known for its excellent detection limits of trace elements − and thus is widely used for failure analysis. − However, in most cases, tested structures are relatively simple and thus a proper analysis and interpretation is often straightforward. In the case of several microns thick and complicated structures with layers as thin as tens of nanometers SIMS failure analysis faces a major problem: mixing effect may prevent proper evaluation of interfaces because signals will have long decay length, and thus it will not be possible to assess whether some intermixing or diffusion occurred.…”