Display Technologies

Emerging display technologies demand high brightness, low power consumption and longer lifetime. Arrays, of self-emitting, micron-sized LEDs or Micro-LED (µLED), are considered a strong contender to replace current OLED or LCD displays.

Phosphor plays a key role to obtain white light as for blue LED + phosphor and near ultraviolet LED + phosphors. In order to improve high bright white LEDs, it is necessary that the whole phosphor particle emits light homogeneously. When measuring with CL the phosphor used as white LED, the area which does not emit light in phosphor particle can be observed. CL system is used for evaluation of non-luminescent area to improve luminescent efficiency and characteristics.

Phase Modulated Spectroscopic Ellipsometry is an excellent technique for the highly accurate characterization of complete TFT-LCD device. The technique allows the determination of film thickness, optical properties but also more complex properties such as graded or anisotropic layers and effect of dopants. In the flat panel industry the pressure to reduce manufacturing coasts is and reliable metrology tools are required to control the different steps of the process. Spectroscopic ellipsometry is a non-destructive technique which presents advanced capabilities and proven reliability tailored for qualification and on-line production control.

Raman spectroscopy is a very well suited technique to determine both Ge fraction and strain in SiGe layers and Si cap layers. Moreover the possibility of using both UV and visible excitation lines on the same instrument is essential to study structures made up of a Silicon cap layer on top of a SiGe layer. The relative Ge content in the constant Si1-xGex layer is calculated from the visible Raman spectrum and the strain of the cap Si layer is derived from the UV Raman spectrum.

Liquid Crystal Modulation Spectroscopic Ellipsometry is an excellent technique for the highly accurate characterization of the compound semiconductor heterostructure AlGaN / GaN. Using the MM-16 spectroscopic ellipsometer it is a straightforward procedure to determine the film thickness and optical dispersions of the complete structure even where the film is several microns thick. The detailed knowledge of the optical parameters of AlGaN alloys is crucial for example for the design of opto-electronic devices. Furthermore, from the optical parameters a calibration curve could be constructed to provide a rapid and efficient determination of the Al content in the AlGaN layers. Thus Spectroscopic Ellipsometry also proves a non-destructive technique for AlGaN alloy composition determination. This method can be equally applied to other compound emiconductors such as SiGe, II-VI semiconductors or classical III-V semiconductors.

The Fluorolog-QM fluorescence spectrometer with an integrating sphere option is an excellent choice for PLQY measurements in NIR. The K-Sphere is very convenient and easy to use, as it couples directly to the sample compartment optics and allows a use of external light sources, such as DPSS lasers, which can be attached to the front of the sample compartment. The sphere has holders for cuvettes, slides and powders that can be easily interchanged. The results demonstrate very good reproducibility and precision for NIR PLQY measurements spanning almost two orders of magnitude. Based on multiple measurements, the demonstrated PLQY standard deviations range from 1.3% for high QY value (77%) to 6.4% for the QY below 1%.

For multilayer structures it is always helpful and often necessary to know the properties of each film. Using the Jobin Yvon UNISEL NIR it is a straightforward procedure to investigate the thickness and optical properties of the complete PDP structure. To ensure high yields in quality and quantity the FF-1000 ellipsometer is dedicated to the flat panel industries with a fully automated large area sample stage able to accept samples up to 1000 mm x 1000 mm. This accurate, automated thin film metrology tool delivers both unique performance and proven reliability for online quality control of production processes.

Spectroscopic Ellipsometers are optical thin film measurement tools for determining film thickness and optical constants (n,k) of thin film structures. They are widely used in the microelectronics, display, photonics, photovoltaics, lighting, optical and functional coating, biotechnology industries. When compared with other optical metrology instruments the unique strength of spectroscopic ellipsometers are based on their highly precise and simple experimental measurements plus physical and material information derived from optical constants characterization.

Emerging display technologies demand high brightness, low power consumption and longer lifetime. Arrays, of self-emitting, micron-sized LEDs or Micro-LED (µLED), are considered a strong contender to replace current OLED or LCD displays.

Phosphor plays a key role to obtain white light as for blue LED + phosphor and near ultraviolet LED + phosphors. In order to improve high bright white LEDs, it is necessary that the whole phosphor particle emits light homogeneously. When measuring with CL the phosphor used as white LED, the area which does not emit light in phosphor particle can be observed. CL system is used for evaluation of non-luminescent area to improve luminescent efficiency and characteristics.

Phase Modulated Spectroscopic Ellipsometry is an excellent technique for the highly accurate characterization of complete TFT-LCD device. The technique allows the determination of film thickness, optical properties but also more complex properties such as graded or anisotropic layers and effect of dopants. In the flat panel industry the pressure to reduce manufacturing coasts is and reliable metrology tools are required to control the different steps of the process. Spectroscopic ellipsometry is a non-destructive technique which presents advanced capabilities and proven reliability tailored for qualification and on-line production control.

Raman spectroscopy is a very well suited technique to determine both Ge fraction and strain in SiGe layers and Si cap layers. Moreover the possibility of using both UV and visible excitation lines on the same instrument is essential to study structures made up of a Silicon cap layer on top of a SiGe layer. The relative Ge content in the constant Si1-xGex layer is calculated from the visible Raman spectrum and the strain of the cap Si layer is derived from the UV Raman spectrum.

Liquid Crystal Modulation Spectroscopic Ellipsometry is an excellent technique for the highly accurate characterization of the compound semiconductor heterostructure AlGaN / GaN. Using the MM-16 spectroscopic ellipsometer it is a straightforward procedure to determine the film thickness and optical dispersions of the complete structure even where the film is several microns thick. The detailed knowledge of the optical parameters of AlGaN alloys is crucial for example for the design of opto-electronic devices. Furthermore, from the optical parameters a calibration curve could be constructed to provide a rapid and efficient determination of the Al content in the AlGaN layers. Thus Spectroscopic Ellipsometry also proves a non-destructive technique for AlGaN alloy composition determination. This method can be equally applied to other compound emiconductors such as SiGe, II-VI semiconductors or classical III-V semiconductors.

The Fluorolog-QM fluorescence spectrometer with an integrating sphere option is an excellent choice for PLQY measurements in NIR. The K-Sphere is very convenient and easy to use, as it couples directly to the sample compartment optics and allows a use of external light sources, such as DPSS lasers, which can be attached to the front of the sample compartment. The sphere has holders for cuvettes, slides and powders that can be easily interchanged. The results demonstrate very good reproducibility and precision for NIR PLQY measurements spanning almost two orders of magnitude. Based on multiple measurements, the demonstrated PLQY standard deviations range from 1.3% for high QY value (77%) to 6.4% for the QY below 1%.

For multilayer structures it is always helpful and often necessary to know the properties of each film. Using the Jobin Yvon UNISEL NIR it is a straightforward procedure to investigate the thickness and optical properties of the complete PDP structure. To ensure high yields in quality and quantity the FF-1000 ellipsometer is dedicated to the flat panel industries with a fully automated large area sample stage able to accept samples up to 1000 mm x 1000 mm. This accurate, automated thin film metrology tool delivers both unique performance and proven reliability for online quality control of production processes.

Spectroscopic Ellipsometers are optical thin film measurement tools for determining film thickness and optical constants (n,k) of thin film structures. They are widely used in the microelectronics, display, photonics, photovoltaics, lighting, optical and functional coating, biotechnology industries. When compared with other optical metrology instruments the unique strength of spectroscopic ellipsometers are based on their highly precise and simple experimental measurements plus physical and material information derived from optical constants characterization.