QI™ Mode

QI™ makes AFM easy - perfect for non-experts, beginners and occasional users

QI mode 4 clicksThe new QI™ mode with its optimized accuracy and operation is able to reach the lowest peak forces down to 10pN. This ensures the lowest tip-sample interaction which preserves the tip and the sample from damage. Particularly for samples that are soft, sticky, brittle or loosely attached to a surface, QI™ mode is the imaging mode of choice. Highly corrugated surfaces, e.g. from tissue, metal or plant samples are now easy to image because of the large Z-range. QI™ mode is superior to conventional AC imaging when studying deep and high-aspect ratio trenches/structures.

Intelligent and automated imaging with just "4 Clicks" is possible. No in-depth knowledge of AFM is needed to operate it and the intuitive, guided settings will save time to get high quality images within minutes.

Quantitative Imaging – an entire force curve behind every pixelIn QI™ mode a complete force-distance curve is recorded at each pixel.

In QI™ mode a complete force-distance curve is recorded at each pixel. By analyzing the curves a comprehensive set of sample properties can be extracted. It delivers real force curves in contrast to other methods using sinusoidal motion and is therefore the only way to get reliable quantitative data with highest resolution.

Perfect direct force control by JPK’s ForceWatch™ technology results in zero setpoint drift. The off-resonant QI™ mode with its linear motion with constant speed, compared to methods from other vendors, guarantees accurate values for stiffness and adhesion.

A major advantage of QI™ is, that no lateral forces act on the sample during scanning. This preserves the sample and the tip and is in particular important when combining QI™ with other modes such as Conductive-AFM.

QI™-Advanced mode option for more detailed analysis bacteriorhodopsin CAFM DNA Block Co-Polymer

For more detailed sample analysis the QI™-Advanced mode is available as an option and provides a map of your sample‘s material properties at a mouse-click - without compromising measurement speed. The newly developed Contact Point Imaging (CPI™) mode as a part of the QI™-Advanced package delivers the height values at zero force. This is a huge benefit particularly for living cells and soft gels if you want to measure the exact topography or the correct volume for example. A topography reconstruction at different interaction forces offers further unique information about your sample.

QI™ is perfect for quantifying biological and chemical interactions, for nano-mechanical studies of polymers or advanced materials, and can be combined with high performance conductive AFM, EFM and KPM. The examples show bacteriorhodopsin at different interaction forces, CAFM on a battery electrode, major and minor grooves of DNA and mapping of a block co-polymer (click on the images for details).

QI™ mode benefits

Qi Benefits 500
  • QI™ mode makes AFM easy and intuitive to operate for everybody
  • Precise force control – ideal for most fragile samples
  • High-resolution images with just “4 clicks” for any sample, particularly samples that are soft and sticky, loosely attached or have steep edges
  • Quantitative images with morphology, mechanical, chemical, optical, magnetic and electrical information such as modulus, adhesion, dissipation, conductivity and more
  • Molecular recognition imaging for localization of binding sites, Contact Point Imaging (CPI™) mode for true topography and 3D ForceCube™ for vertical gradient mapping

QI™ mode comes with the NanoWizard® AFM as a standard. QI™-Advanced mode is an optional add-on software module for nanoscale material properties and can be easily upgraded.