Joska Johannes Broekmaat

High temperature surface imaging using atomic force microscopy

Atomic force microscopy (AFM) is one of the most important tools in nanotechnology and surface science. Because of recent developments, nowadays, it is also used to study dynamic processes, such as thin film growth and surface reaction mechanisms. These processes often take place at high temperature and there is a clear need to extend the current operating temperature range of AFM. This letter describes a heating stage and a modified AFM that extends the maximum operating temperature to 750°C. Atomic step resolution is obtained up to 500°C in ambient and even up to 750°C in vacuum.

Pulsed laser deposited-PZT based MEMS energy harvesting devices

PZT thin films are a huge attraction in the rapid growing MEMS field, especially in the field of energy harvesting. This paper describes the PLD deposited PZT thin film growth and its integration into MEMS energy harvesting devices. We have shown a maximum power output of 51 μW with 63.6 μW/g2 sensitivity for a sinusoidal input excitation. The potential applications of these vibrational harvesters in car tires are explored by applying a shock input excitation.

Fast and gentle side approach for atomic force microscopy

Atomic force microscopy is one of the most popular imaging tools with atomic resolution in different research fields. Here, a fast and gentle side approach for atomic force microscopy is proposed to image the same surface location and to reduce the time delay between modification and imaging without significant tip degradation. This reproducible approach to image the same surface location using atomic force microscopy shortly after, for example, any biological, chemical, or physical modification on a geometrically separated position has the potential to become widely used.

In-situ growth monitoring with scanning force microscopy during pulsed laser deposition

Imaging and mapping “new” land, species, organisms and processes created possibilities to manipulate and control them. Microscopes enabled imaging objects and processes that go beyond the human senses as vision, sense and hearing. This information is required to understand physical and chemical processes such as deposition and growth. Currently, there is also a clear need to monitor the surface morphology during deposition. To image and map (non)conducting surfaces with atomic resolution, Scanning Force Microscopy (SFM) can be used. With physical vapor deposition techniques such as Pulsed Laser Deposition (PLD) thin films of almost any material such as metal oxides can be deposited. Finding the optimum deposition parameters, for material systems, is traditionally done by trial and error. This can be a tedious and time-consuming process especially when information on composition and morphology is lacking during growth. Diagnostic information during deposition of materials such as metal oxides is up to now mostly derived from diffraction methods such as Reflection High Energy Electron Diffraction (RHEED), Surface X-Ray Diffraction (SXRD) and Low Energy Electron Diffraction (LEED). These instruments are based on diffraction and measure the periodic arrangement of the surface atoms. However, the local surface morphology such as the island density, the island size distribution and island shapes can not be directly measured on a microscopic scale as opposed to imaging techniques such as Scanning Probe Microscopy (SPM). This instrument has a high spatial resolution, but is usually not combined with deposition techniques and merely used ex-situ*. This hampers quantitative studies to describe the nucleation and growth because it is difficult to measure the evolution of the same microscopic surface location and the surface morphology evolution could be influenced† by the cooling procedure to room temperature, ambient exposure and ex-situ sample preparation. This thesis describes a setup for in-situ growth monitoring with SFM during Pulsed Laser Deposition (PLD).