CMP for Copper TSV Applications

2010 ◽  
Vol 1249 ◽  
Author(s):  
Max Gage ◽  
Feng Liu ◽  
Kun Xu ◽  
You Wang ◽  
Yuchun Wang ◽  
...  

AbstractThrough-silicon via (TSV) 3-D packaging and integration present many new opportunities and challenges for metals CMP applications. For front-side TSV polishing, challenges include the removal of large amounts of copper overburden, dishing control during copper clearing steps, and removal of large amounts of barrier metal and dielectric layers while still maintaining control over topography and defectivity. Additionally, the choice of barrier material can have significant impact on polishing in terms of the mechanical reliability regarding adhesion between the barrier metal and underlying dielectric layers. This paper will address many of these challenges with an emphasis on innovative technologies for superior process and endpoint controls, such as real-time profile control for thick copper films up to 6μm or more in thickness and automatic endpoint controls for barrier removal and dielectric stopping. The paper will also discuss some salient challenges for back-side TSV polishing, including the handling and polishing of bonded wafer pairs and strategies to minimize handling and polishing damage to the potentially fragile thinned device wafer. Additionally, the development of slurries with highly tunable copper-to-dielectric selectivity will be critical for enabling a wide range of final topographies, depending on requirements for subsequent bonding steps.

2020 ◽  
Vol 11 (11) ◽  
pp. 17-27
Author(s):  
Vadim V. VOEVODIN ◽  
◽  
Marina V. SOKOLOVA ◽  
Viktor R. SOLOV’YEV ◽  
Nikolay Yu. LYSOV ◽  
...  

The results from an experimental study of impulse surface discharge occurring in an electrode system containing a dielectric plate are presented. On one of its sides, the plate had a corona-producing electrode made of 50 mm thick copper foil grounded through a current shunt for measuring the discharge current. On its other side, the plate had a high-voltage electrode, to which the voltage from a pulse generator was applied. The article presents the results from measurements of the initial voltage and the sizes of the surface discharge area in air when applying single voltage pulses with different pulse front steepness in the range 0,1–3,4 kV/ms and amplitude in the range 7–15 kV. The measurements were carried out for different dielectric barrier materials with the e values from 2 to 35. The dielectric barrier thickness was 0,9–1,8 mm. The study results have shown that the initial surface discharge ignition voltage depends essentially on the voltage pulse parameters, whereas the barrier characteristics have a weaker effect on this voltage. It has been determined that the discharge has different discharge zone length and different structure depending on the dielectric barrier properties and applied voltage parameters. The streamer zone sizes decrease with increasing the barrier material e value at the same voltage pulse steepness and increase with increasing the steepness for each barrier material. The data obtained for a wide range of external conditions can be used in numerical modeling of discharge.


2019 ◽  
Author(s):  
Robert Pollice

The rapid development of analytical methods in recent decades has resulted in a wide range of readily available and accurate reaction-monitoring techniques, which allow for easy determination of high-quality concentration-time data of chemical reactions. However, while the acquisition of kinetic data has become routine in the development of new chemical reactions and the study of their mechanisms, not all the information contained therein is utilized because of a lack of suitable analysis tools which unnecessarily complicates mechanistic studies. Herein, we report on a general method to analyze a single concentration-time profile of chemical reactions and extract information regarding the reaction order with respect to substrates, the presence of multiple kinetic regimes, and the presence of kinetic complexities, such as catalyst deactivation, product inhibition, and substrate decomposition.<br>


2011 ◽  
Vol 2011 (DPC) ◽  
pp. 000666-000698
Author(s):  
Christopher Jahnes ◽  
Eric Huenger ◽  
Scott Kisting

To increase performance of semiconductor devices advances in packaging such as chip stacking (3D) and silicon carrier technologies (SoC) are being developed. Adaptation of these packaging fabrication methods offers the ability to incorporate functionality as well as provide memory and power distribution on one IC with increased signal bandwidth. An enabling element in both the stacking and silicon carrier technologies is through silicon vias (TSV) which electrically connect dies to a silicon carrier or via stacked chips (1). Creation of TSV involves via fabrication, wafer thinning and back side wafer finishing, to name a few, some of which are relatively new to semiconductor processing. Furthermore, because the wafer backside is accessible it can now be utilized to route wiring to further increase package density. The focus of this research was to evaluate photo-sensitive spin on dielectric materials (SOD) that can be used as the backside wiring levels, commonly referred to as redistribution layers (RDL) in TSV technologies. The two materials evaluated are; the epoxy based Dow INTERVIA™ 8023 Dielectric and the Benzocyclobutene (BCB) polymer, Dow CYCLOTENE™ 4000 product series. These dielectric materials have low stress and provide good planarization (2). Test vehicles with a chip size of 3.7 cm x 2.26 cm were fabricated with a 6 um wide copper RDL layer using the SOD materials of interest as well as conventional PECVD SiO2/SiN dielectric layers. The large chip size accommodated parallel Cu lines running 1.8 cm long with a spacing of 3 ï&#x81;¬m and represented an aggressive shorting test for the SOD materials. It also enhances chip distortion after thinning and is evaluated for all three test vehicles. Chips were then electrically tested through simulated 260° C reflow cycles (for flip chip joining) and accelerated thermal reliability tests from −55° C to 125° C for 1000 cycles.


1999 ◽  
Vol 564 ◽  
Author(s):  
R. Faust ◽  
Q. Jiang

AbstractThe effect of various barrier materials on the microstructure of electroplated Copper films was investigated. Analysis of the Cu was performed at the as-deposited, room temperature stabilized, and annealed states. It shows that the barrier material can have a dramatic effect on the properties of electroplated Cu.


Author(s):  
Yi Guo ◽  
Robert G. Parker

Tooth wedging occurs when a gear tooth comes into contact on the drive-side and back-side simultaneously. Tooth wedging risks bearing failures from elevated forces. This work studies the nonlinear tooth wedging behavior and its correlation with planet bearing forces by analyzing the dynamic response of an example planetary gear based on a real application of a wind turbine geartrain. The two-dimensional lumped-parameter model [1] is extended to include tooth separation, back-side contact, tooth wedging, and bearing clearances. The simulation results show significant impact of tooth wedging on planet bearing forces for a wide range of operating speeds. To develop a physical understanding of the tooth wedging mechanism, connections between planet bearing forces and tooth forces are studied by investigating physical forces and displacements acting throughout the planetary gear. A method to predict tooth wedging based on geometric interactions is developed and verified. The major causes of tooth wedging relate directly to translational vibrations caused by gravity forces and the presence of clearance-type nonlinearities in the form of backlash and bearing clearance.


Synthesis ◽  
2021 ◽  
Author(s):  
Amit banerjee ◽  
Tomohiro Hattori ◽  
Hisashi Yamamoto

Bimolecular nucleophilic substitution (S N 2) is one of the most known fundamental reactions in organic chemistry to generate new molecules from two molecules. In principle, a nucleophile attacks from the back side of an alkylating agent having a suitable leaving group, most commonly using a halide. However, alkyl halides are expensive, very harmful, toxic and not so stable which makes them problematic for laboratory use. In contrast, trialkyl phosphates are cheap, readily accessible, stable at room temperature, under air, and are easy to handle but rarely used as alkylating agents in organic synthesis. Here, we describe a mild, straightforward and powerful method for nucleophilic alkylation of various nucleophiles such as N-, O-, C- and S- using readily available trialkyl phosphate. The reaction proceeds smoothly with excellent yield and quantitative yield in many cases and covers a wide range of substrates. Further, the rare stereoselective transfer of secondary alkyl groups has been achieved with inversion of configuration of chiral centers (up to >99% ee).


2012 ◽  
Vol 134 (5) ◽  
Author(s):  
André Günther ◽  
Wieland Uffrecht ◽  
Stefan Odenbach

This paper discusses experimental results from a two-cavity test rig representation of the internal air system of a high-pressure compressor. Thermal steady-state measurements of the time-averaged local heat fluxes on both sides of the middle disk are presented for three different flow regimes: pure axial throughflow of cooling air and axial throughflow of cooling air in two directions with a superposed radial inflow of hot air in one cavity. Mass flow ratios between 1/40 < mrad/max < 2/1 are measured. Tests were carried out for a wide range of non-dimensional parameters: Reφ up to 107, Rez up to 2 × 105, and Cw up to −2.5 × 104. In all cases, the shroud is uniformly heated to approximately 100 °C. The local axial heat fluxes are determined separately for both sides of the middle disk from measurements of the surface temperatures with open spot-welded thermo-couples. The method of heat flux determination and an analysis approach calculating the uncertainties and the sensitivity are described and discussed. The local heat flux results of the different flow paths are compared and interpreted by assumed flow structures. The time-averaged heat flux results can be adequately interpreted by flow structures of two toroidal vortices for axial throughflow and a source-sink flow for the radial inflow. The measurements show that the axial heat flux can change direction, i.e., areas exist where the disk is heated and not cooled by the flow. For axial throughflow, a local minimum of heat flux exists on the impinged side in the range of x = 0.65. On the back side, a heating area exists in all tests in the lower half of the disk (x < 0.6) due to recirculated air of higher temperature. This heating area corresponds to the range of the inner vortex and increases with higher axial and rotational Reynolds numbers.


2003 ◽  
Vol 45 (12A) ◽  
pp. A367-A383 ◽  
Author(s):  
E Joffrin ◽  
F Crisanti ◽  
R Felton ◽  
X Litaudon ◽  
D Mazon ◽  
...  

1998 ◽  
Vol 13 (10) ◽  
pp. 2962-2968 ◽  
Author(s):  
W-M. Kuschke ◽  
A. Kretschmann ◽  
R-M. Keller ◽  
R. P. Vinci ◽  
C. Kaufmann ◽  
...  

The textures of thin copper films were determined quantitatively by measuring (111) pole figures with x-ray diffraction. Measurements were performed on a variety of samples, differing in copper film thickness and deposition technique, diffusion barrier material, and the presence or absence of a cap layer. Texture changes due to an annealing treatment were also recorded and correlated with stress measurements by the wafer-curvature technique. It is found that the deposition method (PVD vs CVD) has a strong effect on texture, barrier layer effects range from negligible to significant depending on the barrier material, and the effect of a cap layer is insignificant.


2021 ◽  
Vol 11 (4) ◽  
pp. 2678-2702
Author(s):  
Prabhat Kumar Thella ◽  
V. Ulagamuthalvi

Plants are essential for human life. They help people breathe, provide food, clothing, medicine, and fuel, and also safeguard the environment. Plants can be loaded with medicinal properties and possess active substances that can be used for medical purposes. Several beneficial plant species are disappearing as a result of such factors as global warming, increasing population, professional secrecy, insufficient government support for research efforts, and the lack of public understanding of medicinal plants. It takes time to identify medicinal plants, therefore use professionals to assist you. For better benefit to humankind, a new method to identify and classify therapeutic plants must be developed. Because of the advanced technology in our day and age, medicinal plant identification and classification is an important subject of research in the field of image processing. Feature extraction and classification are the most important components in the process of identifying medicinal plants and classifying them. This research examines methods used in identifying and classifying medicinal plants as well as the medicinal properties of plants that have become increasingly relevant in the recent past. There is a vital importance placed on identifying the suitable medicinal plants in the creation of an ayurvedic medication. In order to identify a medicinal plant, look for these three features: leaf form, colour, and texture. From the both sides of the leaf, there are both deterministic and nondeterministic factors that identify the species. In this study, a combination of traits is designed that is said to identify a single tree the most effectively while minimising errors. The database is made up of scanned photos of both the front and back side of ayurvedic medicinal plant leaves, which is an ayurvedic medicinal plant identification database. In leaf identification, rates as high as 99% have been found when tested on a wide range of classifiers. Extending the prior work by using dried leaves and feature vectors results in identification using which identification rates of 94% are possible. Identification of the correct medicinal plants that goes in to the preparation of a medicine is very important in ayurvedic medicinal industry. The main features required to identify a medicinal plant is its leaf shape, colour and texture. Colour and texture from both sides of the leaf contain deterministic parameters to identify the species. This paper explores feature vectors from both the front and back side of a green leaf along with morphological features to arrive at a unique optimum combination of features that maximizes the identification rate. A database of medicinal plant leaves is created from scanned images of front and back side of leaves of commonly used ayurvedic medicinal plants. The leaves are classified based on the unique feature combination. Identification rates up to 99% have been obtained when tested over a wide spectrum of classifiers. The above work has been extended to include identification by dry leaves and a combination of feature vectors is obtained, using which, identification rates exceeding 94% have been achieved.


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