Donyau Chiang

Submicron-size patterning on the sapphire substrate prepared by nanosphere lithography and nanoimprint lithography techniques

In this paper, we demonstrate and compare the formation of ordered etching masks for submicron-size patterned sapphire substrates through use of the nanosphere lithography and nanoimprint lithography methods. The metal honeycomb network structure and the polymer pillar protrusion structure were obtained from these two methods. Subsequently, the inductively-coupled-plasma reactive ion etching technique was applied to etch the sapphire substrates, and the etchant mixture gases of boron trichloride and argon with the flow rate ratio of 1 to 6 were introduced into the etchant chamber. Two types of submicron -pattern structures were obtained on the sapphire substrate surface after the etching processes were completed. One type of sapphire substrate was the submicron hole array structure and another type was the submicron cone array structure. The working pressure had a considerable effect on the shape geometry and etching rate, and the possible mechanism is discussed.

Monitoring on dry vacuum pump characteristics by mobile device

Dry vacuum pump is a core device in semiconductor and electro-optic industries for vacuum purpose. The pumping characteristics of dry vacuum pump could affect significantly the performance of secondary pump. This article present a method which integrates a mobile device through the remote application program to measure the vacuum pressure, sound, vibration, and power for a dry vacuum pump system. Moreover, the LabVIEW was implemented to the system for pumping experiment control. The pumping characteristics monitored by mobile device can be useful for processing monitor.

Relative reflectivity uncertainty evaluation for a broadband spectrophotometer system

This study aims to analyze the reflectivity measurement uncertainty of a spectrophotometer, with considerations of the perpendicular incidence/reflection, scattering, and artificial manipulation. The operation procedure is designed to utilize a double beam spectrophotometric system, taking advantage of the direct comparison of the luminous intensity to evaluate the uncertainty. The environmental range of the temperature and the relative humidity for the measuring process are controlled to be 23±1.5oC and 50%±10%, respectively. The range for correction reflectivity is 10%-100%. High-reflectivity standard parts are used with the integrating sphere for the calibration. Low-reflectivity standard parts are used along with an integrating sphere for the evaluation when the measurement reflectivity is 0%-9%. The optimal expanded composition uncertainty of the system is found to be 1.2% in the wavelength range of 400 nm-700 nm.

A luminance inspector used for in-line backlight module quality assurance

In this paper, we propose a luminance inspector which uses a CCD camera and neural network models to inspect multiple backlight modules at once. The proposed inspector can display the results at predetermined checked points in real time which is important for in-line quality check. The proposed inspector is more efficient compared to the traditional inspector which examines checked points one by one. Experiments show that the proposed inspector yields satisfactory results.

The development of an automatic scanning path generation method for the spinneret test

An automatic scanning path generation method is developed. The method is based on a 3-axis automatic inspection system which is used to detect the clearance ratio of spinneret plate. The user can rely on this method to automatically generate the scanning path for an unknown spinneret plate in the spinneret test. Then the scanning path can be learned by the inspection system and repeated it for other the same spinneret. Two type spinnerets are introduced in this paper to describe the automatic scanning path generation method. In this paper, the 3-axis automatic inspection system includes a 3-axes motorized linear stage, a telcentric lens, a top light source, a bottom light source, 1 CCD camera and a controlled PC.

Zinc Oxide Column Rod Array Prepared by Inductively Coupled Plasma-Reactive Ion Etching Technology

The nano-scale zinc oxide column rod array is produced by ICP-RIE and nano-sphere lithography. The rod diameter of 54nm is realized.

Surface Formation of Nano- / Micro- Structures on Titanium Alloy Composites using Picosecond Laser Scanning Technology

This study reports on the development of picosecond laser system to titanium alloy surface treatment applications. In the picosecond laser-scanning system, that is based on the fiber-optics laser source and integrated with a designed optics / optical machine design and control technology of scanning system. To analyze the laser material interaction, the laser fluence, pulse repetition frequency of laser source, position of focused points, scan speed and pulse duration were adjusted. After laser surface treatment, the surface roughness and surface morphologies of treated surface were evaluated by using a field emission scanning electron microscope. Moreover, the contact angle measurement was used to analyze the hydrophilic and hydrophobic properties of the treatment surface with micro/ nanostructures.

Development of high-performance parallel exposure I-line UV light source

UV light source and high-pressure mercury lamps are usually used as a projecting light source of foreign exposure light source recently, including a spherical mirror ellipse, an optical integrator, and a parallel lens. The light source system is the most crucial technology to achieve better image quality and better uniformity of light field. High-stability, high-uniformity, and high-parallelism light source should be created to ensure the stability of all processes. In this research, two sets of Flys eye lens are used as an optical integrator for combining with the redesigned parallel lens, which are evaporated AR coating to increase the transmittance of overall optical system up to 80% and the uniformity of light field. Equivalent doublets are also proposed to improve the original design of single parallel lenses for reducing the thickness, curvature, and divergent angle of a single lens so as to enhance the efficiency of light irradiation.

Dual photoresist complimentary lithography technique produces sub-micro patterns on sapphire substrates

Dual photoresist complimentary lithography technique consisting of inorganic oxide photoresist and organic photoresist is applied to produce the sub-micro pit patterns on a sapphire surface. The oxide photoresist is patterned by the direct laser writing and the developed mark size decreases to a smaller value than the laser spot size due to the thermal lithography. The small developed pit diameter is one of the advantages using oxide photoresist. The oxide photoresist possesses strong etching resistance against the oxygen plasma but shows no resistance against the chlorine plasma. The chlorine plasma is a necessary component to etch the sapphire during the ion-coupled-plasma reactive-ion-etching process because of sapphire’s mechanical hardness and chemical stability. However, the characteristics of organic resist SU8 are opposite to that of oxide photoresist and possess moderate resistance against chlorine plasma but show no resistance to oxygen plasma. The thermal and developing characteristics of oxide photoresist are reported here. The dependence of the laser power on the developed mark sizes and morphologies is illustrated by atomic force microscopy. The temperature distribution on the photoresist structure during the laser writing is simulated. Images of patterned pits on the large commercial sapphire substrates are also shown.

Dual-photoresist complementary lithography technique for the formation of submicron patterns on sapphire substrates

Abstract. Dual-photoresist complementary lithography technique consisting of inorganic oxide photoresist and organic photoresist is applied to produce the submicron pit array patterns on a sapphire surface. The oxide photoresist is patterned by direct laser writing, and the developed pit size decreases to a smaller value than the laser spot size due to the thermal lithography. The oxide photoresist possesses strong etching resistance against oxygen plasma but shows no resistance against chlorine plasma. During the ion-coupled-plasma reactive-ion-etching process, chlorine plasma is a necessary component to etch the sapphire. Moreover, the characteristics of organic resist are opposite those of oxide photoresist and possess moderate resistance against chlorine plasma but no resistance against oxygen plasma. The thermal and developing characteristics of oxide photoresist are reported in this study. The dependence of laser power on the developed mark sizes and morphologies is examined by atomic force microscopy. The temperature distribution on the photoresist structure during the laser writing is simulated, and the thermal lithography concept is introduced to explain the effect of power on the developed oxide mark width. Images of patterned pit array on a commercial 4-inch-diameter sapphire substrate are also shown.