Ansys熱分析實例(多芯片組件加散熱器(熱沉)的冷卻分析)

1、三.MCM溫度場穩(wěn)態(tài)分析多芯片組件加散熱器(熱沉)的冷卻分析圖1(a)、圖1(b)所示分別為大功率球柵陣列MCM的截面圖和俯視圖，五個芯片采用倒裝焊方式置于有機基板上，為了增加模塊的散熱能力，在芯片背面上加一熱擴展面。表1所示為各材料的物理屬性。皿2叫Th皿2叫Th鳥科M14ft4ldbTyfnSciSH,.；：八二斗周圍的環(huán)境溫度設(shè)為250C,其中大芯片的功率為25W,熱流密度為60 xl06W/m3；周圍四個小芯片的功率為10W,熱流密度為61.54xlO6W/m3；對流換熱系數(shù)為10W/(mK)。MCM結(jié)構(gòu)參數(shù)和材料屬性模型組件材料尺寸(mm)導(dǎo)熱系數(shù)(W/(mk)-FHLL芯片硅8*8

2、*0.65,5*5*0.6582芯片凸點5Sn/98Pb1O*1O*,6*6,0O.3,Height:0.2,Pitch:0.7536基板聚酰亞胺40*40*1.50.2焊料球96.5Sn3.5Ag26*26,00.6,Height:0.4,Pitch:1.2750PCBFR4100*100*1.58.37,8.37,0.32熱介質(zhì)材料導(dǎo)熱脂Thick:0.151粘接劑粘接劑Thick:0.151.1熱擴展面銅40*40*1.5390熱沉鋁Base:46.5*45.6*1.5,Pinnumber:16,Pinheight:8240分析從而導(dǎo)致器件性能變化和可靠性的下降。熱場分析和設(shè)計是MCM設(shè)

3、計中一個重要的環(huán)節(jié)3。MCM器件中的熱應(yīng)力來自兩個方面，即來自MCM模塊內(nèi)部和MCM模塊所處的外部環(huán)境所形成的熱應(yīng)力，這些熱應(yīng)力都會影響到器件的電性能、工作頻率、機械強度和可靠性。隨著MCM集成度的提高和體積的縮小尤其是對于集成了大功率芯片的MCM其內(nèi)部具有多個熱源，熱源之間的熱耦合作用較強，單位體積內(nèi)的功耗很大，由此帶來的芯片熱失效和熱退化現(xiàn)象突出。有資料表明,器件的工作溫度每升高10C，其失效率增加1倍。因此準(zhǔn)確模擬大功率MCM模塊的三維溫度場分布，并分析掌握其熱特性，有利于指導(dǎo)MCM熱設(shè)計方案的選擇，對提高大功率MCM的可靠性具有重要意義。本文針對某球柵陣列封裝的大功率MCM，提出了一種

4、簡化的熱學(xué)模型，并利用有限元方法借助有限元通用程序ANSYS對其進行三維溫度場的穩(wěn)態(tài)模擬和分析。方案步驟如下：、建模、施加載荷計算、初始溫度及對流系數(shù)（施加于模型外表面，即與空氣接觸的部位）PUIWTSTYPENUMCLiI-n7-HCLiE10ANDEC2200919:48:111.PLlIMTSTYPENUMCUI-HCUE10ANDEC2200919:50:46熱沉的芯片內(nèi)部溫度分布云圖TEMP(AVG)RSYS=O5W=45D2SI=131554NODALSOLUTIONSTEP=1SUE：=1DEC6200922:09:06NODALSOLUTILIN5TEP=1SUE：=1TIME

5、=1TEMPANDEC6200944.52446.192理焊料球(37Sn/63Pb)溫度分布云圖357.86556.19859.53-3簡要分析從以上的分析結(jié)果可以得出：最高溫度出現(xiàn)在中間大芯片區(qū)域，內(nèi)部有源功率芯片是熱源的主要貢獻(xiàn)者，芯片產(chǎn)生的熱量主要沿芯片背面方向傳遞；加散熱裝置來對大功率進行降溫是一種直接有效的方式；另外，在相同條件下，合理的結(jié)構(gòu)布局，如避免大功率器件過分集中不僅能降低結(jié)點溫度最大值，而且能避免熱集中現(xiàn)象，提高組件的可靠性。針對球柵陣列封裝的大功率MCM其內(nèi)部具有多個熱源、耦合作用強、內(nèi)部發(fā)熱量大、溫度高的特點，建立其熱學(xué)模型，在ANSYS平臺下對其進行了穩(wěn)態(tài)模擬分析；

6、結(jié)果表明，增加外部散熱裝置可以大大降低MCM的溫度，是對其進行降溫最直接有效的一種方式；合理布局可以避免熱集中現(xiàn)象。5結(jié)論在MCM器件內(nèi)部，熱場對器件的性能和可靠性有嚴(yán)重的影響，熱場分析是MCM設(shè)計中的重要環(huán)節(jié)。利用ANSYS軟件對一球柵陣列的MCM進行了模擬分析，結(jié)果表明：多芯片組件中,大功率芯片為模塊中熱源的主要貢獻(xiàn)者,芯片內(nèi)最高溫度點位于中間大芯片區(qū)域。MCM幾種降低溫度的方法：加外部散熱裝置是一種直接有效的對MCM進行降溫方式(有散熱裝置的最高溫度是132.823oC，沒有散熱的布局溫度大概達(dá)350C)；在相同條件下，合理的結(jié)構(gòu)布局，能降低結(jié)點溫度最大值，提高MCM組件的可靠性。參考文

7、獻(xiàn)：楊邦朝，張經(jīng)國.多芯片組件技術(shù)及其應(yīng)用.電子科技大學(xué)出版社M.2001：4042李川.MCM的熱分析及復(fù)合SnPb焊點的應(yīng)力應(yīng)變分析D.電子科技大學(xué).四川：成都，2005陳云，徐晨.有限元分析軟件ANSYS在多芯片組件熱分析中的應(yīng)用J.電子工程師2007(2)；張洪信主編有限元基礎(chǔ)理論與ANSYS應(yīng)用.機械工業(yè)出版社，2006.2(2007.1重印)：徐步陸.電子封裝可靠性研究D.中國科學(xué)院上海微系統(tǒng)與信息技術(shù)研究所，博士學(xué)位論文2002命令代碼/BATCH02,-0.0006,VGEN,5,P51XDE,2/SOL/input,menust,tFLST,3,2,6,OR,0.00075,

8、FITEM,3,219FINISH,DE,20FITEM,3,-224/PREP71FITEM,3,8FLST,3,5,6,ORVGEN,3,P51XFLST,2,9,6,ORWPSTYLE,FITEM,3,-9DE,2,0.00075,DE,2,0VSBV,FITEM,3,1760FITEM,2,242/PREP77,P51XFITEM,3,-180BL0CK,0.017,FITEM,2,-250BLOCK,0,0.05NUMCMP,VOVGEN,5,P51X0.02,0,0.017,-0VADD,P51X,0,0.05,0,0.001LU,0.00075,.0001,0.00005,VSE

9、L,S,LOC,5,FLST,3,1,6,OR0BL0CK,0,0.02Z,0.0034,0.004BL0CK,0,0.02DE,1FLST,3,1,6,OR,0.017,0.02,-0.25,0,0.02,0.0019,FITEM,3,7DE,10001,0.00005,VSEL,U,0.0034,VGEN,13,P51FITEM,3,179wpoff,0,0,0.005BLOCK,0,0.02X,0.00127,VGEN,2,P51X075FLST,2,2,6,OR,0,0.02,0.00355,0,0.00875,BL0CK,0,0.00DE,2,0.00505,FLST,3,13,6,

10、O04,0,0.004,0,0.0FITEM,2,195BL0CK,0,0.01RDE,2FLST,3,1,6,OR0015,FITEM,2,2167,0,0.017,0.003FITEM,3,7DE,1BL0CK,0.008VDELE,P51X,55,0.0044,FITEM,3,-19FITEM,3,2015,0.0135,0,0.00,1VSBV,VGEN,13,P51VGEN,6,P51X25,0,0.00015,ALLSEL,ALL3,4X,0.00127,0.00075,BL0CK,0,0.00FLST,2,240,6,BL0CK,0,0.00,0025,0.0085,0.01OR

11、DE,74,0,0.004,0.003wpoff,0,0,0.00FLST,3,6,6,OR35,0,0.00015,FITEM,2,16,0.00425,18DE,2WPAVE,0,0,0FITEM,2,-194BL0CK,0,0.00SPH4,0.00027FITEM,3,201CSYS,0FITEM,2,19625,0.0085,0.015,0.000275,0.0FITEM,3,-206wpoff,0,0,0.00FITEM,2,-21535,0.0036,0.000015VGEN,3,P51X505FITEM,2,217425,BL0CK,0,0.00,0.00075,BL0CK,0

12、,0.02FITEM,2,-241BL0CK,0.0081,0,0.001,0.0000325,0,0.02325,FITEM,2,2515,0.0135,0,0.001,0.0006,FLST,3,1,6,OR0,0.0015,VGLUE,P51X25,0.0036,0.00BL0CK,0,0.00DE,1BL0CK,0.021ET,1,SOLID70425,1,0,0.001,-0.00FITEM,3,17975,0.02325,0,0.MPTEMP,wpoff,0,0,0.0001,-0.0006,VGEN,2,P51X02325,0.0015,0MPTEMP,1,017FLST,3,2

13、,6,OR,0.00875,.0085,MPDATA,KXSPH4,0.00063DE,20FLST,3,1,6,ORX,1,825,0.000635,0.0FITEM,3,177FLST,3,1,6,ORDE,1MPTEMP,003FITEM,3,178DE,1FITEM,3,243MPTEMP,1,0BL0CK,0,0.00VSBV,FITEM,3,219VGEN,8,P51XMPDATA,KX1,0,0.001,0.000176,P51XVGEN,6,P51X,-0.003,0X,2,362,0.0006,FLST,3,1,6,OR,0.00075,VSEL,S,LOC,MPTEMP,B

14、L0CK,0,0.00DE,10Z,0.00505,0.02MPTEMP,1,01,0,0.001,-0.00FITEM,3,179FLST,3,6,6,ORFINISHMPDATA,KXX,3,0.25,1,VSEL,S,LOC,CMSEL,S,_YFITEM,5,242MPTEMP,0Z,0.0034,0.003CMDELE,_YFITEM,5,-243MPTEMP,l,0CMSEL,S,_Y6CMDELE,_Y1CM,_Y,VOLUMPDATA,KXCMDELE,_YFLST,5,2,6,ORVSEL,S,LOC,VSEL,P51X,4,50CMDELE,_Y1DE,2Z,0.0036,

15、0.004XMPTEMP,VSEL,S,LOC,FITEM,5,19525CM,_Y1,V0LMPTEMP,1,0Z,0.0015,0.001FITEM,5,244FLST,5,3,6,ORUMPDATA,KX9CM,_Y,VOLUDE,2CMSEL,S,_YX,5,8.37FLST,5,169,6,VSEL,P51FITEM,5,246CMSEL,S,_Y1MPDATA,KYORDE,2XFITEM,5,-248VATT,Y,5,8.37FITEM,5,7CM,_Y1,V0LCM,_Y,VOLU6,1,MPDATA,KZZFITEM,5,-175UVSEL,P510,5,0.32CM,_Y,

16、VOLUCMSEL,S,_YXCMSEL,S,_YMPTEMP,VSEL,P51CMSEL,S,_Y1CM,_Y1,V0LCMDELE,_YMPTEMP,1,0XVATT,UCMDELE,_Y1MPDATA,KXCM,_Y1,V0L7,1,CMSEL,S,_YVSEL,S,LOC,X,6,1U0CMSEL,S,_Y1Z,0.00505,0.02MPTEMP,CMSEL,S,_YCMSEL,S,_YVATT,CM,_Y,VOLUMPTEMP,1,0CMSEL,S,_Y1CMDELE,_Y1,1,VSEL,MPDATA,KXVATT,CMDELE,_Y10249X,7,1.14,1,FLST,5,

17、2,6,ORCMSEL,S,_YCM,_Y1,V0LMPTEMP,0DE,2CMDELE,_YUMPTEMP,1,0CMSEL,S,_YFITEM,5,195CMDELE,_Y1CMSEL,S,_YMPDE,KXX,6CMDELE,_YFITEM,5,244VSEL,S,LOC,CMSEL,S,_Y1MPDATA,KXCMDELE,_Y1VSEL,U,P51Z,0.00425,0.00VATT,X,6,1VSEL,S,LOC,X5059,1,MPTEMP,Z,0.0019,0.003FLST,5,59,6,OCM,_Y,VOLU0MPTEMP,1,04RDE,6VSEL,CMSEL,S,_YM

18、PDATA,KXCM,_Y,VOLUFITEM,5,176245CMDELE,_YX,8,390VSEL,FITEM,5,-194CM,_Y1,V0LCMDELE,_Y1MPTEMP,252FITEM,5,196UVSEL,S,LOC,MPTEMP,1,0CM,_Y1,V0LFITEM,5,-215CMSEL,S,_YZ,0.0036,0.004MPDATA,KXUFITEM,5,217CMSEL,S,_Y125X,9,240CMSEL,S,_YFITEM,5,-236VATT,SMRT,6VSEL,S,LOC,CMSEL,S,_Y1CM,_Y,VOLU&,1,SMRT,7Z,0,0.0015

19、VATT,VSEL,P510MSHAPE,1,3DCM,_Y,VOLU3,1,XCMSEL,S,_YMSHKEY,0VSEL,0CM,_Y1,V0LCMDELE,_YFLST,5,3,6,OR250CMSEL,S,_YUCMDELE,_Y1DE,2CM,_Y1,V0LCMDELE,_YCMSEL,S,_YVSEL,U,FITEM,5,246UCMDELE,_Y1CMSEL,S,_Y1245FITEM,5,-248CMSEL,S,_YVSEL,S,LOC,VATT,FLST,5,3,6,ORCM,_Y,VOLUCMSEL,S,_Y1Z,0.0034,0.0042,1,DE,3VSEL,P51VA

20、TT,250FITEM,5,216XCM,_Y1,VOLUCM,_Y,VOLUCM,_Y,VOLUFITEM,5,30UCHKMSH,VOVSEL,VSEL,P51FITEM,5,32CHKMSH,VOLU245XFITEM,5,36LUCMSEL,S,_YCM,_Y1,V0LCM,_Y1,V0LFITEM,5,38CMSEL,S,_YVMESH,_Y1UUFITEM,5,719VMESH,_Y1CMDELE,_YCHKMSH,VOCHKMSH,VOFITEM,5,723CMDELE,_YCMDELE,_Y1LULUFITEM,5,727CMDELE,_Y1CMDELE,_Y2CMSEL,S,

21、_YCMSEL,S,_YFITEM,5,730CMDELE,_Y2VSEL,S,LOC,VMESH,_Y1VMESH,_Y1FITEM,5,735VSEL,S,LOC,Z,0,0.0015CMDELE,_YCMDELE,_YFITEM,5,739Z,0.0034,0.003CM,_Y,VOLUCMDELE,_Y1CMDELE,_Y1FITEM,5,74355VSEL,CMDELE,_Y2CMDELE,_Y2FITEM,5,747SMRT,8250VSEL,S,LOC,VSEL,S,LOC,FITEM,5,751CM,_Y,VOLUCM,_Y1,V0LZ,0.00505,0.02Z,0.0015

22、,0.001FITEM,5,755VSEL,UCM,_Y,VOLU9FITEM,5,759244CHKMSH,VOVSEL,SMRT,7FITEM,5,763CM,_Y1,VOLLU249FLST,5,169,6,FITEM,5,767UCMSEL,S,_YCM,_Y1,V0LORDE,2FITEM,5,771CHKMSH,VOVMESH,_Y1UFITEM,5,7FITEM,5,775LUCMDELE,_YCHKMSH,VOFITEM,5,-175FITEM,5,779CMSEL,S,_YCMDELE,_Y1LUCM,_Y,VOLUFITEM,5,783VMESH,_Y1CMDELE,_Y2

23、CMSEL,S,_YVSEL,P51FITEM,5,787CMDELE,_YVSEL,S,LOC,VMESH,_Y1XFITEM,5,791CMDELE,_Y1Z,0.00425,0.00CMDELE,_YCM,_Y1,V0LFITEM,5,799CMDELE,_Y244CMDELE,_Y1UFITEM,5,803CM,_Y,VOLUSMRT,7CMDELE,_Y2CHKMSH,VOFITEM,5,807VSEL,FLST,5,3,6,ORVSEL,S,LOC,LUFITEM,5,811195DE,3Z,0.0034,0.003CMSEL,S,_YFITEM,5,815CM,_Y1,VOLFI

24、TEM,5,2166VMESH,_Y1FITEM,5,819UFITEM,5,242FLST,5,2,6,ORCMDELE,_YFITEM,5,823CHKMSH,VOFITEM,5,-243DE,2CMDELE,_Y1FITEM,5,827LUCM,_Y,VOLUFITEM,5,195CMDELE,_Y2FITEM,5,831CMSEL,S,_YVSEL,P51FITEM,5,244ALLSEL,ALLFITEM,5,835VMESH,_Y1XVSEL,U,P51VSEL,S,LOC,FITEM,5,839CMDELE,_YCM,_Y1,V0LXZ,0.0035,FITEM,5,843CMD

25、ELE,_Y1USMRT,60.00425FITEM,5,847CMDELE,_Y2CHKMSH,VOFLST,5,59,6,OVSEL,S,LOC,FITEM,5,851VSEL,S,LOC,LURDE,6Z,0.0036,0.004FITEM,5,855Z,0.0019,0.003CMSEL,S,_YFITEM,5,17625FITEM,5,8594VMESH,_Y1FITEM,5,-194ASEL,S,EXTFITEM,5,863CM,_Y,VOLUCMDELE,_YFITEM,5,196FLST,5,65,5,OFITEM,5,867VSEL,CMDELE,_Y1FITEM,5,-21

26、5RDE,65FITEM,5,871252CMDELE,_Y2FITEM,5,217FITEM,5,17FITEM,5,875CM,_Y1,V0LSMRT,8FITEM,5,-236FITEM,5,21FITEM,5,883FITEM,5,887ONV,25O,25OFITEM,2,-103FITEM,2,1072FITEM,5,92FITEM,5,891VSEL,S,LOC,1/GOFITEM,5,96FITEM,5,895Z,0.00505,0.02FITEM,2,1033SFA,P51X,1,CFITEM,5,100FITEM,5,899ALLSEL,ALLFITEM,2,-103ONV

27、,10,25FITEM,5,104FITEM,5,903VSEL,S,LOC,7VSEL,S,LOC,FITEM,5,108FITEM,5,907Z,0.00505,0.02FITEM,2,1039Z,0,0.0015FITEM,5,112FITEM,5,911ASEL,S,EXTFITEM,2,-105ALLSEL,ALLFITEM,5,116FITEM,5,915FLST,5,2,5,OR5VSEL,S,LOC,FITEM,5,120FITEM,5,919DE,2/GOZ,0,0.0015FITEM,5,124FITEM,5,923FITEM,5,1045SFA,P51X,1,CASEL,

28、S,EXTFITEM,5,128FITEM,5,927FITEM,5,1069ONV,10,25FLST,5,2,5,ORFITEM,5,132FITEM,5,931ASEL,U,P51ALLSEL,ALLDE,2FITEM,5,136FITEM,5,935XVSEL,S,LOC,FITEM,5,3FITEM,5,140FITEM,5,939ALLSEL,ALLZ,0.0019,0.003FITEM,5,5FITEM,5,144FITEM,5,943VSEL,S,LOC,4ASEL,U,P51FITEM,5,148FITEM,5,947Z,0.00505,0.02ASEL,S,EXTXFITE

29、M,5,152FITEM,5,951ASEL,S,EXTWPSTYLE,ALLSEL,ALLFITEM,5,156FITEM,5,955FLST,5,3,5,OR,1VSEL,S,LOC,FITEM,5,160FITEM,5,959DE,3FLST,5,3,5,ORZ,/0.0015FITEM,5,164ASEL,U,P51FITEM,5,14DE,3VSEL,S,LOC,FITEM,5,168XFITEM,5,1067FITEM,5,1071Z,0,0.0015FITEM,5,172/SOLUFITEM,5,1069FITEM,5,1073ASEL,S,EXTFITEM,5,176FLST,

30、2,4,5,ORASEL,U,P51FITEM,5,1075FLST,5,2,5,ORFITEM,5,180DE,4XASEL,R,P51DE,2FITEM,5,184FITEM,2,15ASEL,U,XFITEM,5,3FITEM,5,188FITEM,2,191068FLST,2,1,5,ORFITEM,5,5FITEM,5,192FITEM,2,23FLST,2,5O,5,ODE,1ASEL,U,P51FITEM,5,196FITEM,2,1066RDE,17FITEM,2,1075XFITEM,5,200/GOFITEM,2,995/GO/SOLUFITEM,5,204SFA,P51X

31、,1,CFITEM,2,997SFA,P51X,1,CFLST,5,169,5,FITEM,5,208ONV,24O,24OFITEM,2,1000ONV,10,25ORDE,169FITEM,5,212FLST,2,8,5,ORFITEM,2,1003VSEL,S,LOC,FITEM,5,40FITEM,5,216DE,8FITEM,2,-100Z,0.0019,0.003FITEM,5,44FITEM,5,220FITEM,2,2974FITEM,5,48FITEM,5,224FITEM,2,31FITEM,2,1009ASEL,S,EXTFITEM,5,52FITEM,5,228FITE

32、M,2,33FITEM,2,-101FLST,5,2,5,ORFITEM,5,55FITEM,5,232FITEM,2,353DE,2FITEM,5,60FITEM,5,236FITEM,2,37FITEM,2,1015FITEM,5,10FITEM,5,64FITEM,5,240FITEM,2,39FITEM,2,-101FITEM,5,1072FITEM,5,68FITEM,5,244FITEM,2,10649ASEL,R,P51FITEM,5,72FITEM,5,248FITEM,2,-106FITEM,2,1021XFITEM,5,76FITEM,5,2525FITEM,2,-102F

33、LST,2,2,5,ORFITEM,5,80FITEM,5,256/GO5DE,2FITEM,5,84FITEM,5,260SFA,P51X,1,CFITEM,2,1027FITEM,2,10FITEM,5,88FITEM,5,264FITEM,5,268FITEM,5,272FITEM,5,276FITEM,5,280FITEM,5,284FITEM,5,288FITEM,5,292FITEM,5,296FITEM,5,300FITEM,5,304FITEM,5,308FITEM,5,312FITEM,5,316FITEM,5,320FITEM,5,324FITEM,5,328FITEM,5,332FITEM,5,336FITEM,5,340FITEM,5,344FITEM,5,348FITEM,5,352FITEM,5,356FITEM,5,360FITEM,5,364F