GHz half wavelength contact acoustic microscopy (HaWaCAM): a feasibility study

The semiconductor industry needs to fit ever more devices per unit area to improve their performance; hence a trend towards increasingly complex structures by varying material combinations and 3D geometries with increasing aspect ratios. The new materials used may be optically opaque, posing problems for traditional optical metrology methods....

Feasibility of 4 GHz half wavelength contact acoustic microscopy (HaWaCAM)

Several methods are being researched to detect and characterize buried nanoscale structures in hard solid samples. The most common acoustic method is acoustic microscopy. An acoustic microscope is based on a single element transducer operating in pulse-echo mode. The acoustic waves are coupled into a sample using a liquid couplant (eg water) and...

Real-Time Estimation of the Tip-Sample Interactions in Tapping Mode Atomic Force Microscopy with a Regularized Kalman Filter

The real-time and accurate measurement of tip-sample interaction forces in Tapping Mode Atomic Force Microscopy (TM-AFM) is a remaining challenge. This obstruction fundamentally stems from the causality of the physical systems. Since the input of the dynamic systems propagates to the output with some delay, and multiple different inputs can...

Thermal nanolithography: A technology compatibility study

TNO and SwissLitho AG were studying the feasibility of a high-throughput, maskless nanopatterning solution for nanostructures down to few nanometers using SwissLitho’s thermal scanning probe lithography (t-SPL)a. The solution enables: Parallelization of nanopatterning on wafers and samples; Non-destructive readout by implementing dynamic mode...

A comprehensive model for transient behavior of tapping mode atomic force microscope

Many investigations have focused on steady-state nonlinear dynamics of cantilevers in tapping mode atomic force microscopy (TM-AFM). However, a transient dynamic model?which is essential for a model-based control design?is still missing. In this paper, we derive a mathematical model which covers both the transient and steady-state behavior. The...

Subsurface Ultrasonic Resonant Force Microscopy for Image-based Overlay Measurement

Scanning Probe Microscopy (SPM) has emerged as a metrology solution for the semiconductor industry enabling high throughput defect review and high resolution 3D metrology. TNO has developed a Subsurface Ultrasonic Resonant Force Microscopy (SSURFM) for non-destructive, high resolution imaging of features buried under one or more layers of...

Improved sub-surface AFM using photothermal excitation

In this paper, we present an AFM based subsurface measurement technique that can be used for overlay and critical dimensions (CD) measurements through optically opaque layers. The proposed method uses the surface elasticity map to resolve the presence and geometry of subsurface structures. To improve the imaging performance of the AFM based...

Improved sub-surface AFM using photothermal excitation

Sub-surface Imaging with Photo Thermal Actuation

In the semiconductor industry, the need for characterization of subsurface features of wafers on a sub-nanometer level becomes ever more important. With Scanning Subsurface Probe Microscopy (SSPM), the smallest features can be measured with high resolution.

Advanced Processing for Quantitative Sub-surface Data Extraction

The TNO Optomechatronics Department is developing various Scanning Probe Microscopy (SPM) techniques, including Sub-surface Atomic Force Microscopy (AFM), as a way to address challenges for nondestructive quality control of optically opaque samples. To support the research and technical developments and to extract quantitative data CD metrology...

Frequency Modulation Sub-surface Atomic Force Microscopy

Elasticity based Sub- surface Atomic Force Microscopy is a promising metrology solution for CD measurements, defect characterization and alignment and overlay applications.

High Resolution SubSurface Probe Microscopy for node5 applications

Imaging of nanoscale structures buried in a covering material is an extremely challenging task, but is also considered extremely important. From fundamental research into living cells structures, to process control in semiconductor manufacturing, many fields would benefit from the capability to image nanoscale structures through arbitrary ...

Image-based overlay measurement using subsurface ultrasonic resonance force microscopy

Image Based Overlay (IBO) measurement is one of the most common techniques used in Integrated Circuit (IC) manufacturing to extract the overlay error values. The overlay error is measured using dedicated overlay targets which are optimized to increase the accuracy and the resolution, but these features are much larger than the IC feature size....

Minimizing tip-sample forces and enhancing sensitivity in atomic force microscopy with dynamically compliant cantilevers

Due to the harmonic motion of the cantilever in Tapping Mode Atomic Force Microscopy, it is seemingly impossible to estimate the tip-sample interactions from the motion of the cantilever. Not directly observing the interaction force, it is possible to damage the surface or the tip by applying an excessive mechanical load. The tip-sample...

Simultaneous AFM nano-patterning and imaging for photomask repair

In this paper we present a new AFM based nano-patterning technique that can be used for fast defect repairing of high resolution photomasks and possibly other high-speed nano-patterning applications. The proposed method works based on hammering the sample with tapping mode AFM followed by wet cleaning of the residuals. On the area where a...