三维网状热功能结构成形机理及多尺度形貌生成控制

Nowadays, microelectronic chips are developing toward micromation, high-power and high level of integration. Meanwhile, the contradiction between high density heat flux and small heat dissipation space is becoming increasingly critical, so a new enhanced heat transfer structure, namely 3D mesh heat functional structure with multi-scale morphology, is proposed and fabricated with multiple slotting saws stacked together. 3D mesh heat functional structure with multi-scale morphology can significantly enhance the heat transfer performance, so it will be an effective way to resolve the contradiction. Then, the machining mechanism of 3D mesh heat functional structure is studied. And, the formation mechanism of the multi-scale morphology, such as microchannels, burrs and some scratches and folds, is analyzed. Furthermore, the influences of the cutting parameters, the cutter geometry parameters and the cutting heat on the multi-scale morphology are investigated, so as to control the formation of the multi-scale morphology. Meanwhile, the impact of the multi-scale morphology on the heat transfer performance, especially the heat efficiency and the flow friction, is studied. Finally, 3D mesh heat functional structure with multi-scale morphology can be designed and manufactured according to the functional requirement. This study provides theoretical basis for the design and manufacture of high performance heat functional structures. As a result, our thermal control technology of microelectronic chips will reach the advanced international level.

目前，热流密度过高而散热空间狭小是高集成微电子芯片面临的一大难题。鉴于此，申请人提出一种表面叠加多尺度形貌的三维网状热功能结构，此结构能够显著强化传热，是解决该难题的一种有效途径。项目将研究多刀叠合同步铣削时三维网状热功能结构的成形机理，揭示微通道、毛刺以及协同生成的刀痕、褶皱等多尺度形貌的生成机理；并建立刀具参数、切削用量、切削热等因素与多尺度形貌的数学模型，从而实现控制生成多尺度形貌；同时研究三维网状热功能结构的传热传质特性以及多尺度形貌对传热效率、流动阻力等特性的影响，从而实现按功能需求主动设计具有多尺度形貌的三维网状热功能结构。项目为高性能热功能结构的设计与制造提供了理论依据，并将使我国微电子热控制技术达到国际先进水平。

目前，热流密度过高而散热空间狭小是高集成微电子芯片面临的一大难题。鉴于此，该项目提出了一种表面叠加多尺度形貌的三维网状热功能结构。并研究了多刀叠合同步铣削时三维网状热功能结构的成形机理，还建立了铣削微通道时的切削力模型。结果表明，刀齿所受切削力由三部分组成：主切削刃与副切削刃参与切削以及切屑横向变形受限制。由于切屑横向变形受到微通道两侧壁面的限制，铣削微通道时的切削力随着径向切削深度的增加而快速增大。同时，揭示了微通道、毛刺以及协同生成的刀痕、褶皱等多尺度形貌的生成机理，为了控制生成多尺度形貌，还研究了刀具参数、切削用量等因素对多尺度形貌的影响，结果表明，当径向切削深度等于或略大于板厚一半时，网孔处形成片状毛刺。当径向切削深度远大于板厚一半时，网孔内形成卷曲毛刺，并且可通过调节切削速度、进给速度以及网孔尺寸进行控制。最后，为了实现按功能需求主动设计三维网状热功能结构，还研究三维网状热功能结构的孔隙率、比表面积等多孔特性对传热性能、流动阻力的影响。结果表明，此结构能够显著强化传热，大体积比表面积和高孔隙率的三维网状热功能结构强化传热效果较好。. 总之，三维网状热功能结构是解决高集成微电子芯片难题的一种有效途径。项目为高性能热功能结构的设计与制造提供了理论依据，并将使我国微电子热控制技术达到国际先进水平。