本文選題：高壓倒裝芯片 + COB光源��； 參考：《深圳大學(xué)》2017年碩士論文

【摘要】：近年來LED(light emitting diode)在照明領(lǐng)域中的應(yīng)用逐漸得到普及,人們對LED提出更小體積、更高亮度、更高功率的要求,這種高功率、高集成度的發(fā)展趨勢給芯片及封裝行業(yè)帶來商機的同時,也讓芯片及封裝行業(yè)面臨越來越大的挑戰(zhàn),其中散熱問題最為引人關(guān)注。散熱不暢導(dǎo)致LED熱量聚集,引起芯片結(jié)溫增大,而結(jié)溫過高會引起波長紅移,造成發(fā)光不均勻、發(fā)光效率下降甚至燒毀失效等危害。所以探討如何提高LED照明的散熱能力是具有很強的現(xiàn)實意義。解決散熱的方案都應(yīng)從先進的封裝技術(shù)及材料上入手,如使用導(dǎo)熱性能更好的陶瓷基板,降低焊接層空洞率,封裝基板表面材質(zhì)與固晶材料的匹配選擇等等,都能在一定程度上提高LED的散熱能力。本文使用普通2835 LED器件制作了電視背光源、使用高壓倒裝LED芯片制作了集成化照明光引擎,并研究了他們的散熱問題。本文的主要工作可分為兩部分:(一)光源制作:使用2835 LED制作了電視背光源組件,使用高壓倒裝LED芯片制作了COB(chip on the board)集成化筒燈光引擎,也采用PFC技術(shù)制作了高壓的PFC-LED器件,并用其制作了相應(yīng)的光源組件;(二)數(shù)據(jù)測試及分析:利用積分球、熱阻分析儀以及ANSYS仿真軟件對所制作的光源進行測試分析。主要研究結(jié)果如下:第一、研究焊接層空洞率對LED背光照明組件熱性能的影響,結(jié)果表明:焊接層空洞率增大,樣品結(jié)溫與熱阻都明顯增大,基本呈線性增長趨勢。當空洞率約為17%時,熱阻增長6.03%,結(jié)溫增長1.74%;當空洞率約為73%時,熱阻增長24.7%,結(jié)溫增長9%。第二、制作了高壓倒裝及常壓倒裝兩款COB光源,并測試了光源的熱阻參數(shù)。與市場上的普通筒燈光源熱參數(shù)對比結(jié)果為:同功率的光源,普通COB光源的結(jié)溫為48.6℃,倒裝COB光源的結(jié)溫為38.83℃,降低了20%;這表明使用倒裝芯片可以有效的降低LED照明組件的結(jié)溫,而且能降低光源集成度,減少成本投入。第三、研究了新型高壓倒裝PFC-LED(package free chip LED)照明組件的熱性能,測試結(jié)果顯示9V高壓倒裝PFC-LED器件的熱阻約為0.342 K/W,近似等于LED芯片的熱阻,遠低于同等電壓下正裝LED芯片的熱阻(約3.5K/W)。本論文使用高壓倒裝LED芯片,制作了兩款可替代市場上現(xiàn)有筒燈光源的倒裝光源,具有使用芯片數(shù)量少、尺寸小且輕薄、便于集成、無需金線鍵合等優(yōu)點。高壓倒裝LED芯片減少了成本、降低了COB光源的尺寸;其次,從封裝工藝上,不僅縮短了散熱通道,而且散熱路徑向下,更有利于冷卻設(shè)計,又可以直接焊接在印刷有電路的基板上,避免進行二次封裝,更有利于散熱;同時提高了可靠性,倒裝芯片無需用金線進行電氣連接,避免了焊點脫開造成的可靠性問題,簡化了封裝工藝。最后對制作的光源進行了相關(guān)的光熱測試分析,為高壓倒裝LED芯片的封裝及應(yīng)用提供了熱學(xué)設(shè)計依據(jù)。
[Abstract]:In recent years, the application of LED(light emitting in the field of lighting has been gradually popularized, people put forward the requirement of smaller volume, higher brightness and higher power for LED. This development trend of high power and high integration brings business opportunities to the chip and packaging industry. Chip and packaging industry is also facing increasing challenges, among which the issue of heat dissipation most attention. Poor heat dissipation leads to the accumulation of LED heat, which results in the increase of chip junction temperature, and the excessive junction temperature will lead to the red shift of wavelength, resulting in non-uniformity of luminescence, the decrease of luminous efficiency and even the failure of burning out and so on. Therefore, it is of great practical significance to discuss how to improve the heat dissipation ability of LED lighting. The solution to heat dissipation should be based on advanced packaging technology and materials, such as the use of ceramic substrate with better thermal conductivity, the reduction of voids in welding layer, the matching selection of surface materials and solid crystal materials, etc. Both can improve the heat dissipation ability of LED to a certain extent. In this paper, 2835 LED device is used to fabricate TV backlight source, and high voltage inverted LED chip is used to fabricate integrated lighting engine, and their heat dissipation problem is studied. The main work of this paper can be divided into two parts: the backlight module of TV is made with 2835 LED, the integrated tube lighting engine of COB(chip on the board) is made by using high-voltage inverted LED chip, and the high-voltage PFC-LED device is made by PFC technology. The corresponding light source components (2) data test and analysis are made. The light source is tested and analyzed by integrating sphere, thermal resistance analyzer and ANSYS simulation software. The main results are as follows: first, the effect of welding layer voids on the thermal performance of LED backlight lighting assembly is studied. The results show that the weld layer voids ratio increases, the junction temperature and thermal resistance increase obviously, and the growth trend is linear. When the void rate is about 17, the thermal resistance increases 6.03, the junction temperature increases 1.74; when the cavity rate is about 73, the thermal resistance increases 24.7and the knot temperature increases 9. Secondly, two COB light sources, high pressure inversion and atmospheric pressure inversion, are made, and the thermal resistance parameters of the light source are tested. The results are as follows: the junction temperature of ordinary COB light source is 48.6 鈩，

本文編號：1825768