Thermal Cycling Reliability of Lead-Free Solders (SAC305 and Sn3.5Ag) for High-Temperature Applications

George, Elviz; Das, Diganta; Osterman, Michael; Pecht, Michael

doi:10.1109/tdmr.2011.2134100

Cited by 52 publications

(26 citation statements)

References 28 publications

(46 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The pores provide more channels to allow the molten solder to penetrate into the internal porous structure and therefore increase the element diffusion to provide a gripping mechanism. This results in the formation of IMC which forms an adhesion between solder and porous Cu as reported by George et al [34].…”

Section: Interfacial Structure Analysismentioning

confidence: 54%

Utilization of a Porous Cu Interlayer for the Enhancement of Pb-Free Sn-3.0Ag-0.5Cu Solder Joint

Jamadon

Tan

Yusof

et al. 2016

Metals

View full text Add to dashboard Cite

Abstract:The joining of lead-free Sn-3.0Ag-0.5Cu (SAC305) solder alloy to metal substrate with the addition of a porous Cu interlayer was investigated. Two types of porous Cu interlayers, namely 15 ppi-pore per inch (P15) and 25 ppi (P25) were sandwiched in between SAC305/Cu substrate. The soldering process was carried out at soldering time of 60, 180, and 300 s at three temperature levels of 267, 287, and 307 • C. The joint strength was evaluated by tensile testing. The highest strength for solder joints with addition of P25 and P15 porous Cu was 51 MPa (at 180 s and 307 • C) and 54 MPa (at 300 s and 307 • C ), respectively. The fractography of the solder joint was analyzed by optical microscope (OM) and scanning electron microscopy (SEM). The results showed that the propagation of fracture during tensile tests for solder with a porous Cu interlayer occurred in three regions: (i) SAC305/Cu interface; (ii) inside SAC305 solder alloy; and (iii) inside porous Cu. Energy dispersive X-ray spectroscopy (EDX) was used to identify intermetallic phases. Cu 6 Sn 5 phase with scallop-liked morphology was observed at the interface of the SAC305/Cu substrate. In contrast, the scallop-liked intermetallic phase together with more uniform but a less defined scallop-liked phase was observed at the interface of porous Cu and solder alloy.

show abstract

Section: Interfacial Structure Analysismentioning

confidence: 54%

Utilization of a Porous Cu Interlayer for the Enhancement of Pb-Free Sn-3.0Ag-0.5Cu Solder Joint

Jamadon

Tan

Yusof

et al. 2016

Metals

View full text Add to dashboard Cite

show abstract

“…More and more lead-free solders are being developed to substitute lead based solders [141], [142], [150]- [152]. The tin-silver-copper (SnAgCu or SAC) solder alloys have been reported to be the best alternative for eutectic SnPb solder in the PV industry [144], [153]. Section 4.1.2 focuses on the thermo-mechanical reliability of mainstream SAC solder alloys which include SAC305, SAC405 and SAC387.…”

Section: Lead Free Soldermentioning

confidence: 99%

A review of photovoltaic module technologies for increased performance in tropical climate

Ogbomo

Amalu

Ekere

et al. 2017

Renewable and Sustainable Energy Reviews

View full text Add to dashboard Cite

The global adoption and use of photovoltaic modules (PVMs) as the main source of energy is the key to realising the UN Millennium Development Goals on Green Energy. The technology -projected to contribute about 20% of world energy supply by 2050, over 60% by 2100 and leading to 50% reduction in global CO 2 emissions -is threatened by its poor performance in tropical climate. Such performance discourages its regional acceptance. The magnitude of crucial module performance influencing factors (cell temperature, wind speed and relative humidity) reach critical values of 90°C, 0.2 m/s and 85%, respectively in tropical climates which negatively impact module performance indices which include power output (PO), power conversion efficiency (PCE) and energy payback time (EPBT). This investigation reviews PVM technologies which include cell, contact and interconnection technologies. It identifies critical technology route(s) with potential to increase operational reliability of PVMs in the tropics when adopted. The cell performance is measured by PO, PCE and EPBT while contacts and interconnections performance is measured by the degree of recombination, shading losses and also the rate of thermo-mechanical degradation. It is found that the mono-crystalline cell has the best PCE of 25% while the Cadmium Telluride (CdTe) cell has the lowest EPBT of 8-months. Results show that the poly-crystalline cell has the largest market share amounting to 54%. The CdTe cell exhibits 0% drop in PCE at high-temperatures and low irradiance operations -demonstrating least affected PO by the conditions. Further results establish that back contacts and back-to-back interconnection technologies produce the least recombination losses and demonstrate absence of shading in addition to possessing longest interconnection fatigue life. Based on these findings, the authors propose a PVM comprising CdTe cell, back contacts and backto-back interconnection technologies as the technology with latent capacity to produce improved performance in tropical climates. Keywordsphotovoltaic modules; solar cell technology; contact technology; interconnection technology; energy payback time; power conversion efficiency; fatigue life. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 2 *Manuscript Click here to view linked References IntroductionThe annual electrical power consumption of the entire planet can be generated by the sun in just one hour [1]. Thus, solar energy is abundant in addition to being clean, sustainable and renewable [2], [3]. Surprisingly, some parts of the world are still struggling to meet their energy needs. It may suffice to say that the regions experiencing energy issues may be having energy conversion problems rather than energy supply problems [2], [4]. It is projected that if 100% exploitation of the energy potentials of the sun ca...

show abstract

“…Clearly, accurate information of the device's temperature over its lifespan is highly desired to enable a regulation of the device's maximum temperature and thermal cycles [23]- [25]. Fundamentally, the effective temperature control in both steady-state and transient conditions can help reduce thermo-mechanical stress and failure rates of the device.…”

Section: Introductionmentioning

confidence: 99%

Real-Time Temperature Estimation for Power MOSFETs Considering Thermal Aging Effects

Chen¹,

Pickert

et al. 2014

IEEE Trans. Device Mater. Relib.

160

View full text Add to dashboard Cite

Abstract-This paper presents a novel real-time power device temperature estimation method which monitors the power MOSFET's junction temperature shift arising from thermal aging effects and incorporates the updated electrothermal models of power modules into digital controllers. Currently, the real-time estimator is emerging as an important tool for active control of device junction temperature as well as on-line health monitoring for power electronic systems but its thermal model fails to address the device's ongoing degradation. Because of a mismatch of coefficients of thermal expansion between layers of power devices, repetitive thermal cycling will cause cracks, voids and even delamination within the device components, especially in the solder and thermal grease layers. Consequently, the thermal resistance of power devices will increase, making it possible to use thermal resistance (and junction temperature) as key indicators for condition monitoring and control purposes. In this paper, the predicted device temperature via threshold voltage measurements is compared with the real-time estimated ones and the difference is attributed to the aging of the device. The thermal models in digital controllers are frequently updated to correct the shift caused by thermal aging effects. Experimental results on three power MOSFETs confirm that the proposed methodologies are effective to incorporate the thermal aging effects in the power device temperature estimator with good accuracy. The developed adaptive technologies can be applied to other power devices such as IGBTs and SiC MOSFETs, and have significant economic implications.

show abstract

Thermal Cycling Reliability of Lead-Free Solders (SAC305 and Sn3.5Ag) for High-Temperature Applications

Cited by 52 publications

References 28 publications

Utilization of a Porous Cu Interlayer for the Enhancement of Pb-Free Sn-3.0Ag-0.5Cu Solder Joint

Utilization of a Porous Cu Interlayer for the Enhancement of Pb-Free Sn-3.0Ag-0.5Cu Solder Joint

A review of photovoltaic module technologies for increased performance in tropical climate

Real-Time Temperature Estimation for Power MOSFETs Considering Thermal Aging Effects

Contact Info

Product

Resources

About