Gold-tin eutectic bonding for hermetic packaging of MEMS devices with vertical feedthroughs

Torunbalcı, Mustafa Mert; Demir, Eyup Can; Dönmez, İnci; Alper, Said Emre; Akın, Tayfun

doi:10.1109/icsens.2014.6985473

Cited by 9 publications

(9 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Due to a number of inherent advantages, Au 0.8 Sn 0.2 eutectic bonding has been heavily researched for WLVP packaging and demonstrated using surrogate proxy wafers [31,32,33,34,35,36], RF MEMS switches [37,38], MEMS resonators [39], and infrared imaging smart sensors [40]. In this approach, Au 0.8 Sn 0.2 is deposited on either the lid or device wafer, and a wettable layer, typically Au, is deposited on the other wafer.…”

Section: Bonding Approachesmentioning

confidence: 99%

“…This deposition approach has been demonstrated for both the IC interconnect [41,51,52] and hermetic MEMS packaging [31,32,33,37,38]. Figure 4 depicts an implementation of this approach in the fabrication of a WLVP for an RF resonator device with vertical feedthroughs [35]. …”

Section: Bonding Approachesmentioning

confidence: 99%

“…Alternating layers of evaporated Au and Sn are used to form the Au 0.8 Sn 0.2 eutectic bond for the wafer-level packaging (WLVP) of a microelectromechanical (MEMS) resonator [35]. ( a ) Cartoon depicting the embodiment; ( b ) Scanning electron microscope (SEM) image of the completed structure including the Au 0.8 Sn 0.2 eutectic bond.…”

Section: Figurementioning

confidence: 99%

“…Reprinted from ref. [35] with permission from the Institute of Electrical and Electronics Engineers (IEEE).…”

Section: Figurementioning

confidence: 99%

See 3 more Smart Citations

Wafer-Level Vacuum Packaging of Smart Sensors

Hilton

Temple

2016

Sensors

View full text Add to dashboard Cite

The reach and impact of the Internet of Things will depend on the availability of low-cost, smart sensors—“low cost” for ubiquitous presence, and “smart” for connectivity and autonomy. By using wafer-level processes not only for the smart sensor fabrication and integration, but also for packaging, we can further greatly reduce the cost of sensor components and systems as well as further decrease their size and weight. This paper reviews the state-of-the-art in the wafer-level vacuum packaging technology of smart sensors. We describe the processes needed to create the wafer-scale vacuum microchambers, focusing on approaches that involve metal seals and that are compatible with the thermal budget of complementary metal-oxide semiconductor (CMOS) integrated circuits. We review choices of seal materials and structures that are available to a device designer, and present techniques used for the fabrication of metal seals on device and window wafers. We also analyze the deposition and activation of thin film getters needed to maintain vacuum in the ultra-small chambers, and the wafer-to-wafer bonding processes that form the hermetic seal. We discuss inherent trade-offs and challenges of each seal material set and the corresponding bonding processes. Finally, we identify areas for further research that could help broaden implementations of the wafer-level vacuum packaging technology.

show abstract

Section: Bonding Approachesmentioning

confidence: 99%

Section: Bonding Approachesmentioning

confidence: 99%

Section: Figurementioning

confidence: 99%

“…Reprinted from ref. [35] with permission from the Institute of Electrical and Electronics Engineers (IEEE).…”

Section: Figurementioning

confidence: 99%

See 2 more Smart Citations

Wafer-Level Vacuum Packaging of Smart Sensors

Hilton

Temple

2016

Sensors

View full text Add to dashboard Cite

show abstract

“…However, it is difficult to fabricate such vertical feedthroughs as they typically need complex via/trench-refill process steps [4,5]. METU-MEMS Center has already reported a new hermetic packaging method, called as the aMEMS process [6][7][8][9][10], which can eliminate all these challenges with a smart combination of simple and traditional MEMS processes without any need for complex via/trenchrefill process steps.…”

Section: Introductionmentioning

confidence: 99%

Die size reduction by optimizing the dimensions of the vertical feedthrough pitch and sealing area in the advanced MEMS (aMEMS) process

Torunbalcı

Alper

Akın

2015

2015 IEEE International Symposium on Inertial Sensors and Systems (ISISS) Proceedings

Self Cite

View full text Add to dashboard Cite

This paper presents the recent reduction of the die size by 44% in the Advanced MEMS (aMEMS) process, now being compatible in size with most of the available through-wafer packaging processes while offering the unique simplicity of the aMEMS process. Size reduction is achieved by reducing the pitch of vertical feedthroughs from 700 µm down to 350 µm and the bonding area width from 300 µm down to 100 µm, approaching to the process limits and still preserving the hermeticity of the package. Both small and large dies, containing the identical resonance sensors inside for benchmarking, are produced together on the same wafer. The cavity pressures of the both dies are measured to be around 1 mTorr even after thermal cycling tests.

show abstract

A method for wafer level hermetic packaging of SOI-MEMS devices with embedded vertical feedthroughs using advanced MEMS process

Torunbalcı¹,

Alper²,

Akın³

2015

J. Micromech. Microeng.

View full text Add to dashboard Cite

This paper presents a novel, inherently simple, and low-cost fabrication and hermetic packaging method developed for SOI-MEMS devices, where a single SOI wafer is used for the fabrication of MEMS structures as well as vertical feedthroughs, while a single glass cap wafer is used for hermetic encapsulation and routing metallization. Hermetic encapsulation can be achieved either with the silicon-glass anodic or Au–Si eutectic bonding techniques. The dies sealed with anodic and Au–Si eutectic bonding provide a low vertical feedthrough resistance around 50 Ω. Glass-to-silicon anodically and Au–Si eutectic bonded seals yield a very stable cavity pressure below 10 mTorr with thin-film getters, which are measured to be stable even after 311 d. The package pressure can be adjusted from 5 mTorr to 20 Torr by using different outgassing, cavity depth, and gettering options. The packaging yield is observed to be around 64% and 84% for the anodic and Au–Si eutectic packages, respectively. The average shear strength of the anodic and eutectic packages is measured to be higher than 17 MPa and 42 MPa, respectively. Temperature cycling, high temperature storage, and ultra-high temperature shock tests result in no degradation in the hermeticity of the packaged chips, proving perfect thermal reliability.

show abstract

Gold-tin eutectic bonding for hermetic packaging of MEMS devices with vertical feedthroughs

Cited by 9 publications

References 5 publications

Wafer-Level Vacuum Packaging of Smart Sensors

Wafer-Level Vacuum Packaging of Smart Sensors

Die size reduction by optimizing the dimensions of the vertical feedthrough pitch and sealing area in the advanced MEMS (aMEMS) process

A method for wafer level hermetic packaging of SOI-MEMS devices with embedded vertical feedthroughs using advanced MEMS process

Contact Info

Product

Resources

About