媒體報導「日本諾貝爾物理學獎得主赤崎勇辭世」，赤崎勇（Isamu Akasaki）帶領學生天野浩（Hiroshi Amano）使用氮化鎵（GaN）成功做出晶體，日亞化學工業員工中村修二（Shuji Nakamura）使用兩人的研究結果，在1993年製造出高亮度的藍光LED。這三人在2014年共同獲得諾貝爾物理獎。
LED的發展早於20世紀早期，一路上都有很多人的研究發展貢獻，歷史可以參考以下科教館專文連結，關鍵的紅光LED在1962年開發出來（Nick Holonyak Jr.），黃光LED在1972年開發出來（M. George Craford），綠光也差不多時間開發出來，直到1993年才將最難的（應該愈晚愈難吧！）才有藍光LED，讓能取代照明的「白光」LED才有可能，到了現在白光LED普及在各種照明設備與顯示器背光模組中，甚至成為主流照明光源，現在厲害的是miniLED、microLED。
2014年諾貝爾物理獎頒給：
Professor Isamu Akasaki, Meijo University and Nagoya University (Japan)
Professor Hiroshi Amano, Nagoya University (Japan)
Professor Shuji Nakamura, University of California, Santa Barbara (USA)
這些發明也推動照明產業發展，其中重要的競爭與推力就是專利（授權、交叉授權訟），當然隨之而來的就是訴訟。
從WIPO檔案中得知，最早藍光LED專利：US4855249（1988年申請、1989年領證），發明人為赤崎勇，發明關於一種使用緩衝層在藍寶石上發展三五族半導體的製程（Process for growing III-V compound semiconductors on sapphire using a buffer layer）。
1. A process for growing a compound semiconductor wherein an organometallic compound and ammonia gas (NH3) are reacted in hydrogen gas (H2) or hydrogen gas mixed with nitrogen gas (N2) to grow epitaxially at least one layer of single crystalline Alx Ga1-x N (0≦x<1) on a sapphire substrate, said process comprising subjecting the sapphire substrate to a heat treatment of brief duration in a atmosphere comprising at least an Al-containing organometallic compound, NH3, and H2 at a temperature lower than the single crystalline AlN growing temperature to deposit a non-single crystalline buffer layer of an AlN compound on the surface of the sapphire substrate and thereafter growing epitaxially at a high temperature said single crystalline Alx Ga1-x N directly on said non-single crystalline buffer layer.
接著中村修二在1992年提出專利申請案，於1994年獲准US5290393，專利關於一種氮化鎵基化合物半導體的晶體生長方法（Crystal growth method for gallium nitride-based compound semiconductor）。
1. A crystal growth method for a gallium nitride-based compound semiconductor, comprising the steps of:
vapor-growing a buffer layer represented by the formula GaX Al1-x N (0>×≦1) having a thickness of 0.001-0.5 μm on a substrate at a first temperature of 200° C. to 900° C.; and
vapor-growing a semiconductor layer represented by the same formula on said formed buffer layer at a second temperature ranging from 900° to 1150° C.
日亞化開發出第一個白光LED，美國專利是US5998925（1997年申請，1999年獲准），發明關於一種具有氮化物化合物半導體和熒光體的發光裝置（Light emitting device having a nitride compound semiconductor and a phosphor containing a garnet fluorescent material），
1. A light emitting device, comprising a light emitting component and a phosphor capable of absorbing a part of light emitted by the light emitting component and emitting light of wavelength different from that of the absorbed light; wherein said light emitting component comprises a nitride compound semiconductor represented by the formula: Ini Gaj Alk N where 0≦i, 0≦j, 0≦k and i+j+k=1 and said phosphor contains a garnet fluorescent material comprising 1) at least one element selected from the group consisting of Y, Lu, Se, La, Gd and Sm, and 2) at least one element selected from the group consisting of Al, Ga and In, and being activated with cerium.
my two cents:
從專利來看科技發展歷史還蠻有趣的。LED專利布局應該很多面向，本篇僅列舉WIPO報導中的部份美國專利。
資料參考：
LED的歷史發展：
LEDinside回顧：LED編年史
2014年諾貝爾物理獎
新聞：
日本諾貝爾物理學獎得主赤崎勇辭世-發明人稱照明革命「藍色LED」
Ron
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