Measurement of periodicity and strain in arrays of single crystal silicon and pseudomorphic Si1−xGex/Si fin structures using x-ray reciprocal space maps

Abstract

Characterization of the periodicity and strain state of an array of lithographically patterned silicon and silicon-germanium alloy on silicon fins using reciprocal space mapping of Bragg diffraction peaks is presented. Various patterned structures with different pitch values of 90 nm, 65 nm, and 42 nm have been studied and data for the 42 nm pitch sample is discussed in this paper. Diffraction from fin arrays is treated kinematically analogous to periodic surface grating structures. Diffraction from the symmetric 004 planes is used to calculate pitch and analyze the pitch walking pattern which appears as harmonic peaks on either side of the fin peaks. Pitch walking refers to the presence of two periodicities in the array due to the lithographic process. Longitudinal scans are evaluated at the fin peak positions to probe into the shape of the fin structure. Nonrectangular fin shapes resulted in peak splitting of the longitudinal scans of higher order fin peaks indicating a finite sidewall slope. Asymmetric 224 planes were analyzed to study the quality and strain-relaxation of the fin structures both parallel and perpendicular to the fin length using reciprocal space mapping techniques.

Visualizable detection of nanoscale objects using anti-symmetric excitation and non-resonance amplification

“…11 and Supplementary Data 1). Because the nanowire structures are widely used in the semiconductor industry [44][45][46][47] , we can use them to mimic the detection of objects in typical wafers with isolated patterns 10 . The nanowire structures can also be embedded in liquid environment to sense free-form objects like viruses and molecule clusters, because liquids do not influence the formation of the EC other than to change the interference period Λ due to the increased refractive index.…”

Dark-field electron holography as a recording of crystal diffraction in real space: a comparative study with high-resolution X-ray diffraction for strain analysis of MOSFETs

“…3 shows the RSM in the (Q x Q z ) plane, acquired in the vicinity of the 004 diffracted beam. A certain amount of strain information can be easily extracted from such RSMs of periodic structures (Medikonda et al, 2014). We observe a signal from two distinct regions in the RSM shown in Fig.…”

State of the Art and Future Perspectives in Advanced CMOS Technology

“…There is no other testing technique that can do this. Therefore, HRXRD is an important method for the characterization of 10 nm and above nodes [ 433 , 434 , 435 , 436 , 437 , 438 , 439 , 440 , 441 , 442 ].…”