High-Resolution XPS and Imaging for Advanced Surface Analysis

High-resolution X-Ray photoelectron spectroscopy and imaging are features of the multi-technique surface analysis equipment, ESCALAB QXi XPS Microprobe.

ESCALAB QXi X-Ray Photoelectron Spectroscopy Microprobe

The Thermo Scientific^TM ESCALAB^TM QXi X-Ray Photoelectron Spectroscopy (XPS) Microprobe satisfies the need for enhanced analytical performance and versatility by fusing quantitative imaging, multi-technique capabilities, and high spectral sensitivity and resolution.

With unmatched flexibility and configurability, the ESCALAB QXi XPS Microprobe is an expandable, optimized multi-technique instrument. It generates excellent spectra in a matter of seconds and is incredibly sensitive.

The robust Thermo Scientific Avantage Data System seamlessly integrates system control, data acquisition, processing, and reporting. Modern technology powered by user-friendly software ensures productivity and world-class outcomes. With its distinct dual detector system, the ESCALAB QXi XPS Microprobe produces exceptional XPS imaging with superior spatial resolution.

ESCALAB QXi X-Ray Photoelectron Spectrometer Microprobe

Monochromated XPS

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With a 500 mm Rowland circle and an Al anode (or dual Al and Ag anode if choosing the dual monochromator option), this twin-crystal, micro-focusing monochromator lets users choose any sample spot size between 200 µm and 900 µm.

Lens and Analyzer

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With a single analyzer path, the same instrument parameters (such as pass energy) can be used for spectroscopy and imaging, as well as the optimized lens and analyzer system on the ESCALAB QXi XPS Microprobe.

Ion Gun

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The ESCALAB QXi XPS Microprobe offers two alternatives for swift and high-resolution depth profiling. It includes the standard EX06 ion gun, optimized for monatomic ion sputtering and ion scattering spectroscopy. Additionally, it provides the option of the monatomic and gas cluster ion source, MAGCIS, which is versatile in performing monatomic ion profiling and cluster ion profiling. Both ion sources are able to be used to perform low energy ion scattering spectroscopy (ISS), which is a technique included as standard on the ESCALAB QXi.

Alignment and Calibration

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To evaluate sensitivity, calibrating the ion source, aligning the X-Ray monochromator, adjusting the linearity of the analyzer energy scale, and figuring out the analyzer’s transmission function, a standards block is supplied. This contains standard reference samples of copper, silver, and gold, a phosphorescent sample for viewwing the X-ray beam, and apertures for ion beam alignment.

Sample Manipulator

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Accurate sample alignment for analysis is made possible by the computer-controlled, 5-axis high-precision translator (HPT). It can be used to automatically swap out sample holders and carry out queued experiments when combined with the recently developed automated sample loading system.

Preparation Chambers

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The Preploc chamber, a hybrid sample entry lock and preparation chamber, has ports that can hold various sample preparation tools, including gas admission, sample parking, ion guns, high-pressure gas cells, and heating/cooling probes.

Flood Electron Source

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When analyzing non-conducting samples with the monochromatic X-Ray source, an electron source coaxial with the analyzer input lens is used for charge compensation in conjunction with a second flood source to supply ions at very low energy to ensure a near zero potential at the surface - eliminating the need for charge referencing in most cases. This assists with data interpretation by removing the uncertainty in the energy calibration when performing insulator analysis.

Detectors

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Two detector systems are installed on the ESCALAB QXi XPS Microprobe: one is designed for spectroscopy and consists of an array of six-channel electron multipliers, while the other is intended for parallel imaging and consists of two channel plates and a continuous position-sensitive detector. The two detector arrangement ensures that each system is optimised for it's function within the spectrometer.

Digital Control

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Since the Windows Software-based Avantage data system controls all analytical functions, the entire analysis process can be carried out remotely if necessary.

Sample Alignment

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The Avantage Data System regulates every movement axis on the sample stage, and a high-definition digital video camera is attached to the device and precisely positioned in relation to the analysis position.

Vacuum System

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To optimize the effectiveness of the magnetic shielding, the analysis chamber is made of 5 mm-thick mu-metal. It is pumped with a turbomolecular pump and a titanium sublimation pump, enabling it to attain ultra-high vacuum of better than 5×10^-10 mbar after bakeout.

Connectivity

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For even quicker measurement area identification, measurement coordinates can be imported into Avantage Data System from specialized microscopy systems using Thermo Scientific Maps Software. By adding XPS spectroscopy and imaging data, surface chemistry and structural data can be directly compared with Maps Software.

Specifications

Source: Thermo Fisher Scientific – Electron Microscopy Solutions