Subnanometer Characterization of Nanoelectronic Devices

Nanoscaled Electrical Characterization

“…On the other hand, C-AFM as well as SSRM have reported ≈1 nm electrical resolution as indication of a higher confinement of the electrical processes within the tip-sample contact area. A notorious case illustrating the difference between physical and electrical contact area relates to SSRM, where the confined pressure transformation resulting from the high force applied to the tip, leads to an electrical contact area 5-10 x smaller than the geometrical one [32]. Figure 3.9a shows the case of SSRM where a thin 0.5 nm oxide is detectable.…”

Fast Fourier transform scanning spreading resistance microscopy: a novel technique to overcome the limitations of classical conductive AFM techniques

“…This structure is composed of seven epitaxially grown Si layers with an increasing boron concentration forming a dopant staircase (figure 2(a)). A thin (0.5 nm) Si0 2 layer sandwiched in between highly boron-doped Si and poly-Si layers is deposited on top in order to evaluate the spatial resolution of the technique [6] (figure 2(c)). A silicide layer (covered by a protective oxide layer deposited at low temperature) is formed on top of the poly-Si layer in order to determine the sensitivity decrease and dynamic range limit of the technique in lowly resistive materials (figure 2(b)).…”

“…In order to be relevant, methods used for this purpose should provide sub-nanometer resolution and high sensitivity over many orders of magnitude and be quantitative. For 20 years, various metrology solutions have been proposed in order to tackle this problem, such as electron holography [1], scanning capacitance microscopy [2], scanning tunneling microscopy [3], and scanning spreading-resistance microscopy (SSRM) [4][5][6]. Among these, SSRM is the only method combining high spatial resolution, sensitivity, and the possibility to perform quantification.…”

“…Various studies have demonstrated that one can provide 2D carrier concentration maps with a spatial resolution down to 0.6 nm and a dopant gradient resolution of 1-2 nm dec −1 , using the SSRM technique in a controlled environment (less than 0.1 ppm of H 2 O and O 2 ) with full diamond tips [6] with a sensitivity ranging over five orders of magnitude and with good quantification accuracy. The possibility to extend the technique towards 3D carrier profiling has also been demonstrated [7][8][9].…”

Scanning spreading resistance microscopy for electrical characterization of diamond interfacial layers

“…SSRM is based on atomic force microscopy (AFM) and is the leading method for quantitative 2D‐carrier profiling, featuring ∼1 nm spatial resolution, a response function covering a wide dynamic range of carrier concentration and the capability for site‐specific analysis . SSRM has been demonstrated as a unique concept for the electrical characterization of semiconductor devices with successful applications toward silicon‐based metal‐oxide semiconductor field‐effect transistors (MOSFETs) , FinFETs , nanowire‐based transistors , and Ge‐based p‐MOSFET devices .…”