因應5G時代的來臨，攜帶式電子及通訊產品在功能上能夠更高速且高效地傳輸訊號，I/O腳的數量及密度皆因而提高，電子元件間距也隨之縮短，使得電子元件間的電磁波干擾(Electromagnetic Interference, EMI)情況變得嚴峻。為了使得電子元件正常運作不受干擾，電磁波屏蔽技術因應而生，將部分元件產生的雜訊導致的電磁波干擾透過屏蔽材料進行吸收、反射以達到其他元件不受干擾的目的。
與此同時，隨著IC構裝尺寸日漸地輕薄短小且組成複雜，對電磁波屏蔽的要求除了優越的電磁波屏蔽效能外，也能達到與構裝貼合共形以優化封裝空間利用率，或是能夠針對局部的電子元件進行電磁波屏蔽。
因此，本研究期望以超音波無噴嘴噴墨將兩種不同導電奈米銀墨水製成燒結銀薄膜作為電磁波屏蔽材料，並分析多種不同製程條件，變因包括基板/陰乾溫度、燒結溫度及噴墨次數等，對燒結銀薄膜的電導率、孔隙率、表面粗糙度以及膜厚等物理性質相互間的影響，以及對電磁波干擾屏蔽效能(EMI SE)的影響。
本研究的最終目標是利用頻譜分析儀、近場探針及XY雙軸電控步進移動平台進行訊號源的大面積訊號強度掃描量測，將燒結銀薄膜作為電磁波屏蔽材料進行對Wi-Fi模組訊號發射天線的部分電磁波屏蔽，得到具有空間解析性的強度分布結果，以模擬實際應用過程中電磁波屏蔽材料破損，利用面掃描訊號強度量測手法找尋材料破損點的分析過程。
研究結果顯示，在膜厚一致的條件下，基板/陰乾溫度(100℃)及燒結溫度(230℃)越高，電導率越高；隨著孔隙率下降，電導率顯著地提高；隨著表面粗糙度下降，電導率些微地提高；隨著電導率增加，電磁波屏蔽效能上升；隨著膜厚增加，電磁波屏蔽效能上升；訊號強度下降至15~20%，解析度約為0.2mm。

In response to the advent of the 5G era, it is required to be capable of effective and high-speed signal transmission for the multi-functional mobile electronics. As a result, the number and density of I/O pins have increased, and the distance between electronic components has been shortened, which makes the EMI (electromagnetic interference) situation between electronic components more and more serious. In order to ensure the normal working of various electronic components, EMI shielding technology was developed to absorb and reflect the EMI caused by the noises generated from some components through the EMI shielding material so that other components are not interfered with.
At the same time, as IC packages become increasingly thinner, smaller, and more complex, requirements for EMI shielding include not only outstanding EMI shielding effectiveness, but also conformal conformity to the package to optimize packaging space utilization, or able to shield local electronic components from EMI.
Therefore, this study uses ultrasonic nozzle-less spray to make sintered silver films from two different kinds of conductive nano silver ink as EMI shields, and analyze how a variety of different process conditions, including substrate/drying temperature, sintering temperature and the times of spray, to affect each other on the physical properties such as conductivity, porosity, surface roughness and film thickness of the sintered silver film, as well as impact on the electromagnetic interference shielding effectiveness (EMI SE).
The ultimate goal of this research is to use a spectrum analyzer, a near field probe and an XY dual-axis electronically controlled stepper platform to conduct large-area signal intensity scanning measurement. Therefore, a spatially resolved intensity distribution result would be obtained. We utilize this characteristic to simply simulate that find the position of the damaged EMI shield during actual application by using sintered silver thin film as an EMI shield to partially shield the Wi-Fi module signal transmitting antenna.
Research results show that under the condition of consistent film thickness, the higher the substrate/shade temperature (100°C) and sintering temperature (230°C), the higher the electrical conductivity; as the porosity decreases, the electrical conductivity increases significantly; as the surface roughness decreases, the electrical conductivity increases slightly; as the electrical conductivity increases, the EMI SE increases; as the film thickness increases, the EMI SE increases. The measurement system of a spectrum analyzer and a near-field probe can achieve the purpose of finding damaged points, and its resolution can be as low as 0.2mm.

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