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The direct depth measurement of structures with aspect ratios between 1 and 4 in the arrays of memory cells represents a major challenge for inline metrology. For 75 nm and larger technology nodes these measurements are carried out using inline AFM using 50±5 nm diameter cylindrical AFM probes. However, for 58 nm and smaller technology nodes these AFM probes are not capable anymore, because the tip diameter is comparable to the diameter of the trench structures themselves. Here we report about the development of 30 nm diameter cylindrical AFM probes suitable for direct depth measurements of 58 nm ground rule (GR) structures. The focus of the development was on tip lifetime, gage capability and throughput in a high volume environment. For the tests two different tip materials—silicon (Si) and electron beam deposited (EBD) carbon were investigated. Both tip types proved to be fully gage capable, and showed no throughput losses in comparison to larger node measurements. The tip lifetime under production cond...

Due to the new challenges accompanying every new shrink node in semiconductor industry new materials have to be implemented or device design has to be adapted—both to realize the intended device that still obeys physical laws. Visualization of these problems is a task of metrologists facing themselves physical borders. Monitoring stress becomes a major challenge arising from new processes applied as well as from worse surface to bulk volume‐ratio or intended implied stress in new concepts of devices. High k‐materials might induce macroscopic stress, which can be monitored on the wafer scale in wafer bow experiments. This unintended stress is even higher in patterned areas but not known in a micrometer scale. The knowledge of microscopic stress—or even nanoscopic stress—is even more important on intended stress implemented in devices and thus target of interest. This paper offers two ways of monitoring sub‐micrometer stress. One is the well established scanning Micro‐Raman technique. The second is a relatively new method called Tip‐Enhanced‐Raman‐Spectroscopy (TERS). Both methods have their advantages but also challenges. The results of the easy to use scanning Micro‐Raman technique need to be interpreted and information needs to be unfolded. Whereas the challenge of Tip‐Enhanced‐Raman‐Spectroscopy lies in the experimental skills: handling a scanning‐probe‐microscope‐tip in a Micro‐Raman beam with the perspective of having a resolution restricted only by the SPM‐diameter or even smaller.