Volume 27(1) - Winter 2011

We have been making a series of papers for thin-film analysis techniques for characterization of crystalline qualities and crystal structures using High Resolution XRD (HR-XRD), or characterization of layer structures, such as film thickness, etc., using X-ray reflectivity (XRR) method. An X-ray analytical technique for the evaluation of particle/pore sizes will be explained in this paper.

Small Angle X-ray Scattering (SAXS) technique is a technique mostly used for characterization of the size distributions of particle sizes dispersed in liquid medium, or those of pores/textures in porous bulk samples. Due to the sample configuration, the analysis is used to be performed using transmission geometry through sample bodies. However, in applying this technique to thin film samples, a reflection geometry is required since the absorption due to thick substrates is the great obstacle to detect the weakly scattered signals from thin films or their surfaces. This situation is inevitable since nano- or sub-micron scaled surface textures or structures formed on sample surfaces are the main target of this analysis.

In this paper, a general feature of SAXS measurement and analysis with the transmission geometry will be briefly mentioned first. Then, details of SAXS measurement/analysis technique in transmission geometry applied for thin film samples will be shown together with the applications to the functional thin film samples.
 

The MiniFlex II benchtop XRD system is widely used in a variety of fields. Its small size, high angular performance and dependable design lend it the flexibility necessary for this range application. Over time, our users have started to place higher demands on the system. There has been diversification in the types of samples being measured, and laws and regulations have changed. For example, in asbestos analysis, it is necessary to detect trace phases of crystal in a short time. In order to respond to these requirements, Rigaku has made it possible to use the D/teX Ultra with the MiniFlex II. D/teX Ultra is a high-speed, one-dimensional X-ray detector that enables the MiniFlex II to perform high speed/high intensity measurement, obtaining higher angular and energy resolutions than previously possible. Using the D/teX Ultra, users can collect high quality data in a short time. This report details these new capabilities and provides examples of how they have been applied.
 

X-ray diffractometry (XRD) and differential scanning calorimetry (DSC) are widely used to measure changes in the physical and chemical states (e.g., phase transition, crystallization, dehydration, decomposition) of solid substances. Rigaku Corporation’s instrument for simultaneous measurements of XRD and DSC (hereafter referred to as the XRD-DSC) is configured with a general purpose X-ray powder diffractometer to which a DSC is attached. As an instrument capable of providing information on thermal and structural changes from a single measurement of samples weighing on the order of a mere several mg to less than 20 mg, it has earned a good reputation in research and development involving pharmaceuticals, complexes, liquid crystals, catalysts, high polymers, and electronic materials. The features of the XRD-DSC and the data obtained using a high-speed one-dimensional X-ray detector were presented last year in this journal. This article introduces the features of an XRD-DSC on which a PILATUS 100K/R high-speed, high-sensitivity two-dimensional detector is mounted, as well as the latest data obtained with this device.
 

The thermogravimetry-differential thermal analysis (TG-DTA) is a simultaneous measurement technique where the material’s mass changes as well as energy changes are measured during heating and the macroinformation on the physico-chemical changes of the material can be concluded from the obtained data.  However, in order to fully understand the reactions that have occurred, it has to depend on the information obtained from other measurement techniques. Such as in TG-DTA where a mass loss is associated with an endothermic reaction, then we can conclude that reactions such as dehydration, evaporation, sublimation, degradation or reduction have occurred. Although we can conclude the kind of reactions that have occurred if the information on the material’s structural formula, degradation temperature or water adsorption percentages are present, but on the contrary, it is difficult to draw conclusions if the material is unknown. In this case, combining TG-DTA with other measurement techniques is helpful in understanding the structural changes in the material and if the volatilized chemical species are known, then the chemical reaction process that can be derived will be a useful information. The combination of TG-DTA and evolved gas analysis is one of the complex measurements. Evolved gas analysis (EGA) is defined as a measurement technique where the gases which evolved from the sample upon heating are qualitatively and quantitatively measured as a function of temperature. It is often combined with other thermal analysis techniques rather than used as a stand-alone module.

Examples of EGA detection analyzers are mass spectrometer (MS), thermal conductivity detector (TCD), flame ionization detector (FID) and infrared spectrometer (IR). Among these, the MS is characterized as highly sensitive and can perform measurements rapidly. During the recent years, the TG-DTA-MS is a combination of MS and TG-DTA where it can also be used as a standard module.
 

The compact and safe designed MiniFlex II benchtop X-ray diffractometer provides the user with a remarkable degree of freedom—it can be installed almost anywhere you wish. This system will prevent user from radiation exposure by locking the door while X-rays are on. These features, among others, make it a very userfriendly system.

In contrast, the D/teX Ultra, a high-speed, solid state 1-D detector, is typically employed as a key component in high-end multipurpose systems. It shortens measurement time requirements considerably and makes it possible to collect high-intensity data.

The D/teX Ultra detector, previously available only with high-end “big iron” systems has been reengineered to be compatible with the compact MiniFlex II. Rigaku is pleased to introduce the MiniFlex II+D/teX Ultra, a compact, convenient benchtop system with the data collection power of a high-end instrument.
 

The dual-wavelength system is attractive to crystallographers, chemists and material scientists who deal with various kinds of samples. It is critical to select an X-ray wavelength that is best suited to intended samples.

It is well known that selecting a suitable X-ray source is essential to successful experiments. However, changing the X-ray source requires tedious and time consuming steps.

A newly developed dual-wavelength rotating anode system, MicroMax DW (Dual Wavelength), makes it possible to use 2 different wavelengths without exchanging the target and therefore greatly extended its applicable area. It eliminates troublesome operations such as a target replacement by placing two types of materials on the surface of one target. With MicroMax DW, switching an X-ray source to another can be accomplished without any difficulty. Furthermore, this system works well on tiny crystals because a high brilliance X-ray beam can be irradiated to a sample.