本文選題：大功率半導(dǎo)體器件 + 接觸熱阻　； 參考：《北京工業(yè)大學(xué)》2015年碩士論文

【摘要】：功率VDMOS器件具有開(kāi)關(guān)速度快、輸入阻抗高、驅(qū)動(dòng)能力強(qiáng)、不存在二次擊穿現(xiàn)象等優(yōu)點(diǎn),廣泛應(yīng)用于自動(dòng)控制、混合動(dòng)力系統(tǒng)、軍工、航天等領(lǐng)域。由于VDMOS器件的廣泛應(yīng)用,使得VDMOS器件的使用可靠性成為人們關(guān)注的重點(diǎn)。針對(duì)功率VDMOS器件的使用可靠性問(wèn)題,本文進(jìn)行了高溫加速壽命實(shí)驗(yàn)。在實(shí)驗(yàn)過(guò)程中,大功率VDMOS器件出現(xiàn)突然燒毀的現(xiàn)象。分析表明,器件發(fā)生燒毀的原因是由于接觸熱阻變大。進(jìn)而,本文對(duì)接觸熱阻展開(kāi)研究。接觸熱阻的產(chǎn)生是由于VDMOS器件與散熱片之間由于接觸界面之間存在間隙,以及導(dǎo)熱系數(shù)不匹配等原因?qū)е碌摹＝佑|熱阻的存在使得熱量在器件散熱通路上傳播過(guò)程受到阻礙,器件內(nèi)部熱量難以及時(shí)發(fā)散,結(jié)溫升高。隨著工藝水平的不斷提高,大功率器件內(nèi)部熱阻可降至0.1~0.4℃/W左右,而接觸熱阻甚至?xí)哂谄骷䶮嶙鑳杀兑陨稀＝佑|熱阻阻礙器件散熱,導(dǎo)致器件結(jié)溫升高,使得器件使用可靠性下降,嚴(yán)重時(shí)將導(dǎo)致器件燒毀。針對(duì)以上兩個(gè)問(wèn)題,本文做出以下研究:一、對(duì)大功率VDMOS進(jìn)行了150℃、180℃、200℃、230℃高溫加速壽命實(shí)驗(yàn),通過(guò)測(cè)量IRFM260器件在加速條件下的敏感參數(shù)(導(dǎo)通電阻Ron、閾值電壓VGS、柵極電流IGS,截止漏電流IDSR,漏源電流IDSS(導(dǎo)通狀態(tài)))退化規(guī)律及失效時(shí)間,分析失效分布情況,從而得到正常應(yīng)用條件下,大功率VDMOS器件的壽命、失效率等可靠性參數(shù)。二、對(duì)接觸熱阻的無(wú)損測(cè)量問(wèn)題進(jìn)行研究。本文利用接觸熱阻隨接觸應(yīng)力變化這一機(jī)理,利用Phase11熱阻分析儀對(duì)樣品的總熱阻進(jìn)行測(cè)量,建立接觸熱阻與接觸應(yīng)力的數(shù)學(xué)模型,并利用測(cè)得的數(shù)據(jù)對(duì)接觸熱阻進(jìn)行提取,進(jìn)一步驗(yàn)證接觸熱阻與接觸應(yīng)力之間的函數(shù)關(guān)系,并在ICEPAK熱模擬軟件中對(duì)不同接觸應(yīng)力下的接觸熱阻進(jìn)行熱模擬。三、本文還對(duì)接觸熱阻的溫度特性及退化特性進(jìn)行了研究。將樣品置于可控溫的恒溫平臺(tái)上,以恒溫平臺(tái)的溫度變化來(lái)模擬環(huán)境溫度的變化,在恒溫平臺(tái)溫度變化的同時(shí)測(cè)量樣品的總熱阻,提取接觸熱阻并對(duì)比溫度變化過(guò)程中接觸熱阻的變化情況。當(dāng)大功率器件安裝到散熱片上之后,經(jīng)過(guò)長(zhǎng)期的使用,接觸熱阻會(huì)發(fā)生變化,變化速率、變化程度又將如何?本文針對(duì)這一問(wèn)題做出研究,本文利用三只樣品進(jìn)行高溫加速壽命實(shí)驗(yàn),實(shí)驗(yàn)選擇150℃、140℃、130℃進(jìn)行高溫加速壽命實(shí)驗(yàn),首先測(cè)量樣品初始接觸熱阻阻值,以接觸熱阻變化量達(dá)到20%為失效判據(jù),測(cè)得高溫情況下三只樣品的失效時(shí)間,并利用Arrhenius模型外推室溫下樣品的失效時(shí)間。高低溫溫度循環(huán)情況又會(huì)如何影響接觸熱阻?本文對(duì)接觸熱阻樣品進(jìn)行高低溫溫度循環(huán)實(shí)驗(yàn),實(shí)驗(yàn)高溫限制選定為120℃,低溫限制選定為-30℃,循環(huán)周期為2h,其中保持時(shí)間為40min。在以上條件下進(jìn)行高低溫溫度循環(huán)實(shí)驗(yàn),探究接觸熱阻的變化情況。
[Abstract]:Power VDMOS devices have many advantages, such as high switching speed, high input impedance, strong driving capability and no secondary breakdown phenomenon. They are widely used in automatic control, hybrid power system, military industry, aerospace and other fields. Due to the wide application of VDMOS devices, the reliability of VDMOS devices has become the focus of attention. Aiming at the reliability of power VDMOS devices, an accelerated life test at high temperature is carried out in this paper. In the process of experiment, the high power VDMOS device suddenly burns out. The analysis shows that the cause of device burnout is due to the increase of contact thermal resistance. Furthermore, the contact thermal resistance is studied in this paper. The thermal contact resistance is caused by the gap between the VDMOS device and the radiator and the mismatch of the thermal conductivity. The existence of contact thermal resistance hinders the process of heat propagation in the heat dissipation path of the device, and it is difficult for the internal heat of the device to dissipate in time, and the junction temperature rises. With the continuous improvement of the process level, the internal thermal resistance of high power devices can be reduced to about 0.4 鈩，

本文編號(hào)：2003404