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本次研究以磁控濺鍍法製備鎢酸鎂薄膜螢光體，製程變數包括操作功率、
工作壓力、氧氣 / 氬氣比例以及基板溫度等， 對沈積薄膜的相有重大的
影響。 薄膜中發現α、β等主要相存在以及 MgO 次要相的出現。α相在
低沈積速率下較易生成，而β相在高氧濃度以及高沈積速率的狀況下較易
產生。 由 SEM 的觀察，薄膜顯示一個相當緻密的柱狀結構。另外研究中
發現製程變數對薄膜表面型態有些顯著的影響。對於沈積後的高溫退火處
理， 結果發現對陰極發光有極大的改善，其中退火條件在 750 ℃或更高
的溫度之下有較大的效果，原因是在退火後的薄膜有β相的出現，造成陰
極發光特性的大幅提昇。然而高溫退火處理卻造成了薄膜附著性的劣化，
這是由於在薄膜 / 基材間因退火處理所造成的孔洞所致。 我們假設孔洞
的生成是高溫退火時界面擴散的結果。對於退火後的薄膜，陰極發光光譜
的量測結果發現顯示一個 460 埃的放射光譜。
Magnesium tungstate (MgWO4) thin film phosphors prepared by
the R. F. magnetron sputter deposition were
characterized. Processing parameters such as operation powder,
working pressure and oxygen/argon ratio were found to play an
important role in affecting the phase present in the as-
deposited films. a andβ-MgWO4 were determined as the major
phases and MgO as a minor phase in the film studied. α-MgWO4
phase was stable for films grown at low deposition rates,
whereas β-MgWO4 phase appeared to be a dominant phase
for films grown at high oxygen concentrations or high
deposition rates. SEM observations indicated the films
were rather dense and grown in a columnar array. The effect
of processing parameters on film morphology was not
noticeable. A post-deposited annealing treatment was
found to improve the luminescence property, with
the temperatures at 750 ℃ or above being the most
effective. It appeared that when b-MgWO4 present in the film
after annealing, the cathodoluminescence property was greatly
improved. However, the high-temperature annealing was shown to
deteriorate the film adhesiveness due to the presence of
annealing-induced voids at the film/substrate interface,
presumably resulted from the interdiffusion at high
temperatures. Cathodoluminescence spectrum measurement
results showed that the emission was about 460 angstrom for the
as-annealed films studied.
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