雙層a-Si/Cu100-xZrx及a-Si/Ta無機記錄薄膜應用於藍光可寫一次光碟之研究

A study of a-Si/Cu100-xZrx and a-Si/Ta Bilayer Inorganic Recording Film for Write-once Blue-ray Disk

蕭志翔(Chih-Hsiang Hsiao)

指導教授 ： 郭博成

共同指導教授 ： 唐維泰 ； 蔣東堯

國立臺灣大學/工學院/材料科學與工程學研究所/碩士(2008年)

https://doi.org/10.6342/NTU.2008.02661

摘要

在可寫一次光碟的記錄媒體材料中，有機染料已經被應用在CD-R 及DVD-R 很多年，但是由於有機染料在藍光波長的光吸收率太低以及碟片旋轉塗佈中所產生的不均勻性，有機染料並不適用於短波長的可寫一次光記錄媒體。因此，無機的記錄材料被視為取代有機染料的方式之一，其中以半導體-金屬雙層薄膜做為藍光可寫一次光記錄材料為目前的研究主流。因此本研究嚐試以a-Si/Cu100-xZrx bilayer及a-Si/Ta bilayer兩種方式做為無機可寫一次光碟片之記
錄層材料。由Tx熱分析實驗結果顯示a-Si/Cu100-xZrx bilayer 在Zr含量為11.5%~34.6%及42.4%時，反射率均有兩階段的變化，第一階段大約是從150℃到350℃，第二階段是從400℃到500℃。而Zr含量為38.1%時僅有一階段的反射率變化，溫度大約在350℃。a-Si/Ta bilayer反射率的變化溫度有兩個階段。第一個階段約為120℃到300℃，第二階段約為350℃到450℃。a-Si/Cu100-xZrx初鍍薄膜(x=11.5~34.6)之TEM 電子繞射分析顯示具有Cu的結晶相，經過350℃、30 分鐘熱處理後會形成Cu3Si 相與ZrSi2相共存的雙相結構，經過450℃、30 分鐘熱處理後仍為Cu3Si 相與ZrSi2相共存，但可以發現明顯的晶粒成長現象。a-Si/Cu100-xZrx初鍍薄膜(x=38.1、42.4)之TEM電子繞射分析顯示初鍍薄膜應為非晶或微晶結構，分別以300℃、30分鐘及400℃、30 分鐘熱處理後，則變成Cu3Si、ZrSi2與Cu10Zr7三相共存的結構。再分別經過400℃、30 分鐘及500℃、30 分鐘熱處理後，Cu3Si 相消失，且從TEM明視野相片中可以看到很明顯的晶粒成長現象。經由TEM電子選區繞射圖分析得知，a-Si/Ta bilayer初鍍薄膜為Ta 的結晶相。經過320℃、30 分鐘熱處理後產生Si 及Ta2Si 的結晶相。經過480℃、30分鐘後的熱處理後形成Si、Ta2Si、Ta 和TaSi2共存的結構。a-Si/Cu100-xZrx雙層薄膜(x=11.5~42.4)在藍光下對比值均超過15%，可以滿足光學對比值之要求。a-Si(6.4nm)/Ta(9nm) bilayer薄膜在BD碟片測試中，以1X寫入速度寫入時，最佳的jitter值為5.6%，以4X寫入速度寫入時最佳的jitter值為7%。

關鍵字

藍光光碟 ； 薄膜 ； 光學記錄材料

並列摘要

The organic dye had been applied in CD-R and DVD-R as write-once recording material for
many years, however, due to the low absorption and physical defects during spin-coating process,
the organic dye hardly be used in blue-ray optical recording. Recently, the inorganic write-once
materials, especially the semiconductor/metal bilayer thin films are studied for blue-ray optical
recording media application. In this study, a-Si/Cu100-xZrx bilayer and a-Si/Ta bilayer thin films
were studied. Thermal analysis shows that the a-Si/Cu100-xZrx bilayer films (x=11.5~34.6 and 42.4)
have two phase transition temperatures , 150℃~350℃ and 400℃~500℃. However, the
a-Si/Cu61.9Zr38.1 bilayer has only one phase transition temperature, and the temperature is about 350
℃. The a-Si/Ta bilayer film also has two phase transition temperature, 120℃~300℃ and 350℃
~450℃.
The TEM analysis shows that the as-deposited a-Si/Cu100-xZrx bilayer films (x=11.5~34.6)
have Cu phase, and it would transform to the Cu3Si and ZrSi2 coexisting phases after annealing at
350℃ for 30mins. After annealing at 450℃ for 30mins, the structure is still the Cu3Si and ZrSi2
coexisting phases with a large grain size.
As-deposited a-Si/Cu100-xZrx bilayer film (x=38.1 and42.4) are amorphous or nanocrystal
structures, and it would transform to the Cu3Si, ZrSi2 and Cu10Zr7 coexisting phases after annealing
at 300℃, 30mins for x=38.1 bilayer film and 400℃ ,30mins for x=42.4 bilayer film, respectively.
V
The Cu3Si phase disappeared and grain size enlarged after annealing at 400℃, 30mins for x=38.1
bilayer film and 500℃ ,30mins for x=42.4 bilayer film, respectively.
As-deposited a-Si/Ta bilayer has a crystalline Ta structure, and it would transform to Si and
Ta2Si coexisting phases the after annealing at 320℃ for 30mins. As the annealing temperature is
further increased to 480℃,it would transform to the Si, Ta, Ta2Si and TaSi2 coexisting phases.
The dynamic tests shows that the jitter value of a-Si/Ta is 5.6% under 1X BD formation and 7%
under 4X BD formation.

並列關鍵字

blue-ray disc ； thin film ； recording media

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