The improvement of P2O5-V2O3-Fe2O3 glass frit application in light-emitting diode sealing

• Main Authors: CHENG,AN-CHIH, 鄭安志
• Other Authors: HUANG,CHUN-CHIEH
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/k82yc7

碩士 === 正修科技大學 === 電機工程研究所 === 104 === This Study analyzes the vehicle equipped in the thermal-seal-covered light-emitting diode (LED); use the vehicle and glass powder to produce the frit with proper viscosity range. The Study starts by mixing P2O5, V2O3and Fe2O3powders; then, take the same amount of glass powder, additionally added with Bi2O3,PbO and Fe2O3ingredients with specific percentages to be the comparison sample; the weight percentage of ingredients (Bi2O3, PbO and Fe2O3) is approx. 20%. Study result indicates that the glass powder additionally added ingredients (Bi2O3, PbO and Fe2O3) will rise up the glass transition temperature (Tg) along with the increase of Fe2O3; we thus didn’t select this glass powder as the sealing glass powder. Adjust the basis of expandable glass powder by adding both PbTiO3and Nd2O3 ingredients. The experiment result indicates that adding the PbTiO3can modify the thermal expansion coefficient from 15(10E-6/℃) to 4.8(10E-6/℃); adding Nd2O3 will improve the absorption of near-IR within the waveform between 750nm~850nm; after adding these two minor ingredients, the DSC and XRD analysis shows that it doesn’t change the glass-softening point of glass powder. Make the synthetic glass powder into frit, select the carrier C with good flow ability and low-degrease temperature as the major component; after testing, the frit with 70% solid-colloidal has a brilliant spot-forming character; frit with 50% solid-colloidal is suitable for screen printing. DSC analysis on the improved glass-powder crystals shows that the glass transition temperature (Tg) is approx. 350℃, over the EDS it ensures that there is no frit left. By performing the electrical and optical measurement on the sealed LED, due to the operating temperature, the thermal-seal-up of grit somehow has jeopardized the LED crystals a little bit, which makes Vf drifts slightly on the I-V chart; yet, the drift data is minor. The radiant flux is inferior than epoxy-seal-up; main reason causing it is that the sealed frit makes a little overflow and that result in some light is absorbed during the light-producing process.