車用IC構裝工程之FEM分析與可靠度驗證–以MCP脫層缺陷為例

Abstract

為滿足車用IC高品質、高結構強度及多功能的要求，因此具有整合性多功能之多晶片構裝，遂成為主流。為了節省空間及增進效能，利用MCP（Multi Chip Package）構裝結構方式，達到車用IC的要求，但由於構裝結構趨於複雜化，且構裝體必須承受，更多來自於外在的環境應力，其複雜的行為，可能會引起構裝體內部產生脫層缺陷，造成內部元件受損。 鑑於以往的研究中，對於構裝工程大都著重於分析軟體的模擬，極少針對實際車用構裝可靠度環境驗證，搭配模擬軟體來進行研究，如何發展出一個高可靠度的車用IC構裝體，以達到品質與成本的最佳組合，提高產品競爭力，遂成為一個重要的研究課題。 本研究採用有限元素（FEM）分析軟體，模擬及探討多晶片構裝體，以環氧樹脂(EMC / Epoxy Molding Compound)為其唯一變數，分析承受溫度循環負載時，所產生的翹曲（Warpage）變形與相關應力應變之變化，並搭配實際車規可靠度驗證，同時量測翹曲變化，與有限元素模擬值進行相互比對，探討脫層與翹曲變形的關聯性。

To fulfill the requirements for high quality, high structure and multi-function in Automobile industry, thus the IC with multi-function in multi-chips package structure is becoming the mainstream in Automobile application. By Multi Chip Package (MCP) assembly structure, it would provide the space saving and efficiency improvement to satisfy the automobile requirements. However, with the more and more complicated assembly structure, the IC package would sustain more outside stress. These complicated activities would cause the delamination problem and damage the inner device in its body. The research is simulated and studied the structure of multi-chip base on the Finite Element Method（FEM）, and the Epoxy Molding Compound（EMC）is the only variable factor. The research provides the measurement of warpage and the force related variation under the cyclic loading at ambient temperature. In addition, the reliability test which are according to automobile industry standards measure the change of warpage at meantime. Finally it would be discussed the correlation between delamination and warpage by comparing with the simulated data of finite elements. Base on the experiences of previous research, most assembly engineering would focus on the simulation analysis, but few reliability and environment tests which accompany the simulation software to research are applied to product assembly on real automobile industry. How to develop a highly reliable IC package in automobile field and to achieve the optimum composing in cost and quality for the product competitiveness enhancement has become an important research topic.