An Optimized 300mm BCB Wafer Bonding Process for 3D Integration

2010 ◽  
Vol 1249 ◽  
Author(s):  
Pratibha Singh ◽  
John Hudnall ◽  
Jamal Qureshi ◽  
Vimal Kumar Kamineni ◽  
Chris Taylor ◽  
...  
Keyword(s):  
Wafer Bonding ◽  
Bonding Process ◽  
Acoustic Microscopy ◽  
Cross Linking ◽  
Process Conditions ◽  
Optimization Approach ◽  
3D Integration ◽  
Razor Blade ◽  
Integration Schemes ◽  
The Impact

AbstractWafer bonding using benzocyclobutene (BCB) has been discussed in the past for three-dimensional (3D) integration. This paper reports the development and characterization of a manufacturable BCB bonding process for 300 mm wafers using standard 300 mm tools. A systematic optimization approach has been developed to characterize the bulk properties of the BCB film that can be applied to various integration schemes. We specifically discuss one such application—handle wafer bonding. BCB bonding for a range of cross-linking levels has been investigated. The cross-linking level of BCB before bonding is determined using an infrared (IR) variable angle spectroscopic ellipsometer (VASE) technique. The impact of the BCB film preparation and bonding condition on bond quality is characterized using scanning acoustic microscopy (SAM) , IR microscopy, a razor blade test, and four-point bend methods. Based on the results, an optimum cross-linking level for BCB film before bonding was determined for 300 mm wafers to obtain void-free and dendrite-free bonds. Wafers bonded using the optimized BCB process conditions have successfully sustained backgrinding, dry thinning, and standard BEOL metallization steps.

Wafer Bonding Using Dielectric Polymer Thin Films in 3D Integration

2001 ◽  
Vol 710 ◽  
Author(s):  
Y. Kwon ◽  
J.-Q. Lu ◽  
R. P. Kraft ◽  
J. F. McDonald ◽  
R.J. Gutmann ◽  
...  
Keyword(s):  
Thin Films ◽  
Thermal Stability ◽  
Wafer Bonding ◽  
Polymer Thin Films ◽  
Three Dimensional ◽  
Bonding Process ◽  
3D Integration ◽  
Razor Blade ◽  
Chemical Structures ◽  
Dielectric Polymer

ABSTRACTA key process in our approach to monolithic three-dimensional (3D) integration is the bonding of 200-mm wafers using dielectric polymer thin films as bonding glues. After discussing the desired properties of polymer thin films, we describe how bonding protocols are evaluated using silicon and glass wafers. After bonding, the fraction of bonded area was inspected optically and a razor blade method was used to indicate bonding strength. Thermal stability and bonding integrity were evaluated using thermal cycling and backside grinding and polishing. To date, we have studied benzocyclobutene (BCB), Flare™, and methylsilsesquioxane (MSSQ) and Parylene-N as bonding glues. Wafer pairs bonded using BCB showed a larger fraction of bonded area, and those using Flare indicated higher thermal stability. Both BCB and Flare glues provided good bonding integrity after backside grinding tests. Changes in the chemical structures of BCB and Flare glue during bonding were analyzed using FTIR in order to understand the bonding mechanism and to improve the bonding process.

The Role of Wafer Bonding in 3D Integration and Packaging

2010 ◽  
Vol 2010 (1) ◽  
pp. 000355-000360
Author(s):  
James Hermanowski ◽  
Greg George
Keyword(s):  
Wafer Bonding ◽  
Process Integration ◽  
3D Integration ◽  
3D Ic ◽  
Integration Schemes ◽  
Front End

There are numerous process integration schemes currently in place for the implementation of 3D-IC. Via first, via middle, via last along with back end of line (BEOL), front end of line (FEOL) and other variations of these approaches. This work will explore the role of wafer bonding, both permanent and temporary, in the fabrication of 3D-IC. Additionally, the materials and process flows used for these processes will be examined in detail.

(ECS Meeting PRiME 2020) High TEC copper to connect copper bond pads for low temperature wafer bonding

2020 ◽  
Author(s):  
Anh Van Nhat Tran ◽  
Kazuo Kondo ◽  
Tetsuji Hirato
Keyword(s):  
Wafer Bonding ◽  
Room Temperature ◽  
Three Dimensional ◽  
Copper Surface ◽  
Bonding Process ◽  
3D Integration ◽  
High Thermal Expansion ◽  
Lower Temperature ◽  
Bond Pads ◽  
High Thermal Expansion Coefficient

Copper to copper wafer hybrid bonding is the most promising technology for three-dimensional (3D) integration. In the hybrid bonding process, two silicon wafers are aligned and contacted. At room temperature, these aligned copper pads contain radial-shaped nanometer-sized hollows due to the dishing effect induced by chemical-mechanical polishing (CMP). These wafers are annealed for copper to expand and connect upper and lower pads. This copper expansion is key to eliminate the radial-shaped hollows and make copper pads contacted. Therefore, in this research, we investigated the new high thermal expansion coefficient (TEC) electrodeposited copper to eliminate dishing hollows at lower temperature than that with conventional copper using the combination of new additive A and three other additives. The TEC of new electrodeposited copper is 25.2 x 10-6 oC-1, 46% higher than conventional copper and the calculated contact area of copper surface at 250oC with 5 nm dishing depth is 100%.

A Cost and Yield Analysis of Wafer-to-wafer Bonding

2015 ◽  
Vol 2015 (DPC) ◽  
pp. 000401-000418 ◽  
Author(s):  
Amy Palesko ◽  
Chet Palesko
Keyword(s):  
Wafer Bonding ◽  
Bonding Process ◽  
Technology Selection ◽  
Total Cost ◽  
Trade Offs ◽  
Multiple Variables ◽  
Die Bonding ◽  
Time Required ◽  
The Cost ◽  
The Impact

When a product requires the bonding of two die or wafers, there are a number of methods that may be used. Not only does the type of bonding process itself have to be selected, but it must also be determined whether the items being bonded will be in wafer or die form. This paper will focus on wafer-to-wafer bonding, which has the highest throughput compared to die-to-wafer and die-to-die bonding; it also has the potential to be the lowest cost option if proper yields are achieved. This paper will introduce the background and general pros and cons of wafer-to-wafer, die-to-wafer, and die-to-die bonding. Activity based cost modeling will be used to construct a generic flow of a wafer-to-wafer bonding process. The process flow will be divided into a series of activities, and the total cost of each activity will be identified. The cost of each activity will be determined by analyzing the following attributes: time required, amount of labor required, cost of material required (consumable and permanent), tooling cost, depreciation cost of the equipment, and yield loss associated with the activity. The model will be used to explore multiple variables that affect the total cost of the wafer-to-wafer bonding process, including: incoming wafer cost, incoming wafer defect density, time required for the dicing process, time required for the bonding process, cost of the equipment for the bonding process, and the yield of the bonding process. First, a sensitivity analysis will be conducted to determine the impact each variable has on the total cost. Then scenarios will be created to conduct trade-offs between multiple variables. Only one, generic wafer-to-wafer bonding model will be created, but there will be enough variables to accurately reflect different bonding methods in use by the industry today. Methods for bonding two wafers together will also be discussed in the paper, as well as the cost and yield issues associated with each. An example of these methods are thermo compression bonding and direct bonding. The goal of this analysis will be to understand the cost and yield drivers associated with wafer-to-wafer bonding, and to determine scenarios in which wafer-to-wafer bonding is a suitable, cost effective technology selection.

Effects of Bonding Process Parameters on Wafer-to-Wafer Alignment Accuracy in Benzocyclobutene (BCB) Dielectric Wafer Bonding

2005 ◽  
Vol 863 ◽  
Author(s):  
F. Niklaus ◽  
R.J. Kumar ◽  
J.J. McMahon ◽  
J. Yu ◽  
T. Matthias ◽  
...  
Keyword(s):  
Integrated Circuits ◽  
Layer Thickness ◽  
Wafer Bonding ◽  
Three Dimensional ◽  
Bonding Process ◽  
Alignment Accuracy ◽  
Wafer Level ◽  
Bonding Parameters ◽  
Wafer Pair ◽  
The Impact

AbstractWafer-level three-dimensional (3D) integration is an emerging technology to increase the performance and functionality of integrated circuits (ICs). Aligned wafer-to-wafer bonding with dielectric polymer layers (e.g., benzocyclobutene (BCB)) is a promising approach for manufacturing of 3D ICs, with minimum bonding impact on the wafer-to-wafer alignment accuracy essential. In this paper we investigate the effects of thermal and mechanical bonding parameters on the achievable post-bonding wafer-to-wafer alignment accuracy for polymer wafer bonding with 200 mm diameter wafers. Our baseline wafer bonding process with softbaked BCB (∼35% cross-linked) has been modified to use partially cured (∼ 43% crosslinked) BCB. The partially cured BCB layer does not reflow during bonding, minimizing the impact of inhomogeneities in BCB reflow under compression and/or slight shear forces at the bonding interface. As a result, the non-uniformity of the BCB layer thickness after wafer bonding is less than 0.5% of the nominal layer thickness and the wafer shift relative to each other during the wafer bonding process is less than 1 μm (average) for 200 mm diameter wafers. The critical adhesion energy of a bonded wafer pair with the partially cured BCB wafer bonding process is similar to that with soft-baked BCB.

scholarly journals Investigation of the functional network modifier loading on the stoichiometric ratio of epoxy resins and their dielectric properties

2021 ◽  
Author(s):  
Istebreq A. Saeedi ◽  
Sunny Chaudhary ◽  
Thomas Andritsch ◽  
Alun S. Vaughan
Keyword(s):  
Glass Transition ◽  
Dielectric Properties ◽  
Electrical Properties ◽  
Epoxy Resins ◽  
Functional Network ◽  
Cross Linking ◽  
Network Modifier ◽  
Epoxy Resin System ◽  
The Cross ◽  
The Impact

AbstractReactive molecular additives have often been employed to tailor the mechanical properties of epoxy resins. In addition, several studies have reported improved electrical properties in such systems, where the network architecture and included function groups have been modified through the use of so-called functional network modifier (FNM) molecules. The study reported here set out to investigate the effect of a glycidyl polyhedral oligomeric silsesquioxane (GPOSS) FNM on the cross-linking reactions, glass transition, breakdown strength and dielectric properties of an amine-cured epoxy resin system. Since many previous studies have considered POSS to act as an inorganic filler, a key aim was to consider the impact of GPOSS addition on the stoichiometry of curing. Fourier transform infrared spectroscopy revealed significant changes in the cross-linking reactions that occur if appropriate stoichiometric compensation is not made for the additional epoxide groups present on the GPOSS. These changes, in concert with the direct effect of the GPOSS itself, influence the glass transition temperature, dielectric breakdown behaviour and dielectric response of the system. Specifically, the work shows that the inclusion of GPOSS can result in beneficial changes in electrical properties, but that these gains are easily lost if consequential changes in the matrix polymer are not appropriately counteracted. Nevertheless, if the system is appropriately optimized, materials with pronounced improvements in technologically important characteristics can be designed.

The Lateral Cross-Linking of Polyurethane Using Grafted Epichlorohydrin and the Impact on the Tensile and Thermal Properties

2016 ◽  
Vol 37 (2) ◽  
pp. 323-331 ◽  
Author(s):  
Yong-Chan Chung ◽  
Byung Hee Lee ◽  
Jae Won Choi ◽  
Byoung Chul Chun
Keyword(s):  
Thermal Properties ◽  
Cross Linking ◽  
The Impact

A Method for Evaluating Intensity of Water Cavitation Peening Processing

2011 ◽  
Vol 675-677 ◽  
pp. 747-750
Author(s):  
B. Han ◽  
Dong Ying Ju ◽  
Xiao Guang Yu
Keyword(s):  
Residual Stress ◽  
Process Capability ◽  
Diffraction Method ◽  
Spring Steel ◽  
Bubble Collapse ◽  
Plastic Layer ◽  
Process Conditions ◽  
X Ray Diffraction ◽  
Near Surface ◽  
The Impact

Water cavitation peening (WCP) with aeration, namely, a new ventilation nozzle with aeration is adopted to improve the process capability of WCP by increasing the impact pressure induced by the bubble collapse on the surface of components. In this study, in order to investigate the process capability of the WCP with aeration a standard N-type almen strips of spring steel SAE 1070 was treated byWCP with various process conditions, and the arc height value and the residual stress in the superficial layers were measured by means of the Almen-scale and X-ray diffraction method, respectively. The optimal fluxes of aeration and the optimal standoff distances were achieved. The maximum of arc height value reach around 150μm. The depth of plastic layer observed from the results of residual stresses is up to 150μm. The results verify the existence of macro-plastic strain in WCP processing. The distributions of residual stress in near-surface under different peening intensity can provide a reference for engineers to decide the optimal process conditions of WCP processing.

Structuring of Silicon Wafer Surfaces on the Sub-100 nm Scale by Hydrogen Plasma Treatments

2003 ◽  
Vol 788 ◽  
Author(s):  
R. Job ◽  
Y. Ma ◽  
A. G. Ulyashin
Keyword(s):  
Hydrogen Plasma ◽  
Structural Defects ◽  
Process Conditions ◽  
Force Microscopy ◽  
Czochralski Silicon ◽  
Atomic Force ◽  
Nano Structures ◽  
Plasma Treatments ◽  
The Impact ◽  
Wafer Surfaces

ABSTRACTHydrogen plasma treatments applied on standard Czochralski silicon (Cz Si) wafers cause a structuring of the surface regions on the sub-100 nm scale, i.e. a thin ‘nano-structured’ Si layer is created up to a depth of ∼ 150 nm. The formation of the ‘nano-structures’ and their evolution in dependence on the process conditions was studied. The impact of post-hydrogenation annealing on the morphology of the structural defects was studied up to 1200 °C. The H-plasma treated and annealed samples were analyzed at surface and sub-surface regions by scanning electron microscopy (SEM), atomic force microscopy (AFM), and μ-Raman spectroscopy.

Sign in / Sign up

Export Citation Format

Share Document