As emphasized in the International Technological Roadmap for Semiconductors (ITRS), two-dimensional carrier profiling is one of the key elements in support of technology development. Scanning spreading resistance microscopy (SSRM) has been demonstrated to have attractive concentration sensitivity, an easy quantification, and is applicable to complementary metal–oxide–semiconductor Si and InP structures. Its commercial implementation and availability together with an ample supply of appropriate (diamond based) tips has enabled its more widespread use during recent years. In this article we propose a number of measurement procedures and software tools for its more reliable and fast routine application. First we present a program for the automatic generation of calibration curves and the fast quantification of one-dimensional and two-dimensional resistivity (and carrier) profiles. In view of the large tip consumption, a fast evaluation and calibration of newly mounted conductive tips is a major issue. Furthermore, the fast extraction of the underlying carrier distributions leads to an easier data interpretation. We also propose an overview of the implementation and of the applications of the scanning spreading resistance spectroscopy (SSRS), where a full I–V curve is collected at each measurement point. SSRS proves to be particularly interesting to study the point-contact characteristics (in scanning mode) and simplifies significantly the junction delineation. SSRS can also be used for the selection of the optimal bias settings for the quantification procedure.

This article discusses the results obtained from an extensive comparison set up between nine different European laboratories using different two-dimensional ͑2D͒ dopant profiling techniques ͑SCM, SSRM, KPFM, SEM, and electron holography͒. This study was done within the framework of a European project ͑HERCULAS͒, which is focused on the improvement of 2D-profiling tools. Different structures ͑staircase calibration samples, bipolar transistor, junctions͒ were used. By comparing the results for the different techniques, more insight is achieved into their strong and weak points and progress is made for each of these techniques concerning sample preparation, dynamic range, junction delineation, modeling, and quantification. Similar results were achieved for similar techniques. However, when comparing the results achieved with different techniques differences are noted.

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It is well known that the electrical junction depth position measured along a beveled surface, as is routinely done in the spreading resistance probe ͑SRP͒ technique, is shallower than the corresponding metallurgical junction as seen by secondary ion mass spectrometry. The amount of on bevel junction shift ͑i.e., the difference in electrical on bevel versus metallurgical junction depth͒ in SRP has previously been attributed to a combination of material removal during the beveling ͑i.e., one-dimensional zero-field Poisson model͒ and pressure enhanced carrier spilling ͑enhanced permittivity͒. Recently the interest in the application of two-dimensional electrical characterization techniques such as scanning capacitance microscopy, with virtually zero pressure, and scanning spreading resistance microscopy, with a much smaller contact, on beveled surfaces has emerged in order to meet the needed resolutions. The data from these techniques, however, indicate that our present understanding of the carrier-spilling phenomenon is incomplete. Based on a detailed intercomparison of the depth profiles on well-calibrated, junction isolated samples, the shapes of the calibration curves, current-voltage curves, and device simulations, an improved carrier spilling model is proposed that incorporates a uniform surface state density of 5ϫ10 12 /eV/cm 2 , with a neutral ͑Fermi-pinning͒ level of 0.28 eV above mid-band gap.