2020, Vol.30, No.5

Journal of the Korean Crystal Growth and Crystal Technology 2023 KCI Impact Factor : 0.19

pISSN : 1225-1429 / eISSN : 2234-5078
https://journal.kci.go.kr/jkcgct

Ring-shaped SiC (Silicon carbide) polycrystals used as an inner material in semiconductor etching equipment was manufactured using the PVT (Physical Vapor Transport) method. A graphite cylinder structure was placed inside thegraphite crucible to grow a ring-shaped SiC polycrystal by the PVT method. The crystal polytype of grown crystal were analyzed using a Raman and an UVF (Ultra Violet Fluorescence) analysis. And the microstructure and components of SiC crystal were identified by a SEM (Scanning Electron Microscope) and EDS (Energy Disruptive Spectroscopy) analyses. The grain size and growth rate of SiC polycrystals fabricated by this method was varied with temperature variation in the initial stage of growth process.

To analyze and describe the behavior and mechanisms occurring in the thermal oxidation process of AlN, bulk AlN single crystals were thermally treated with different temperatures. As a result, it was confirmed that full-scale oxidation of bulk AlN and growth of Al-oxide occurred from the temperature of 800°C, which confirmed that the weight% of O elements tended to increase while the N elements decreased with increasing the temperature. In the case of thermal treatment at 900°C, the grown Al-oxides were merged with neighboring Al-oxides and began to form α-Al2O3 poly-crystals. During thermal treatment at the temperature of 1000°C, hexagonal pyramidal shaped poly-crystalline α-Al2O3 was clearly observed. Through the X-ray diffraction pattern analysis, the changes of surface crystal structure according to the temperature of bulk AlN were investigated in detail.

The printed electronics field using ink-jet printing technology is in the spotlight as a next-generation technology,especially ink-jet 3D printing, which can simultaneously discharge and precisely control various ink materials, has been actively researched in recent years. In this study, complex structure of an insulating layer and a conductive layer was fabricated with photo-curable silica ink and PVP-added Cu nano ink using ink-jet 3D printing technology. A precise photocuredsilica insulating layer was designed by optimizing the printing conditions and the rheological properties of the ink,and the resistance of the insulating layer was 2.43 × 10¹³ Ω·cm. On the photo-cured silica insulating layer, a Cu conductive layer was printed by controlling droplet distance. The sintering of the PVP-added nano Cu ink was performed using an IPL flash sintering process, and electrical and mechanical properties were confirmed according to the annealing temperature and applied voltage. Finally, it was confirmed that the resistance of the PVP-added Cu conductive layer was very low as 29 μΩ·cm under 100°C annealing temperature and 700 V of IPL applied voltage, and the adhesion to the photo-cured silica insulating layer was very good.