Fixed Abrasive Technology for STI CMP on a Web Format Tool

2001 ◽  
Vol 671 ◽  
Author(s):  
Alexander Simpson ◽  
Laertis Economikos ◽  
Fen-Fen Jamin ◽  
Adam Ticknor
Keyword(s):  
Slow Rate ◽  
Removal Rate ◽  
Deposition Process ◽  
Good Choice ◽  
Process Window ◽  
Integration Schemes ◽  
Trench Isolation ◽  
Planarization Process ◽  
Oxide Removal ◽  
Fixed Abrasive

ABSTRACTShallow trench isolation (STI) requires a high quality oxide with superior fill capability provided by High Density Plasma (HDP) oxide. Unfortunately, the HDP deposition process can create large within die topographies that are difficult to polish directly using conventional silica slurries. As a result, etch back integration schemes have traditionally been incorporated for STI polish. A more revolutionary approach is the use of Fixed Abrasive (FA) CMP [1]. FA CMP allows direct STI polish with good planarization/process stability, eliminating the need for prior etch back. The planarization efficiency is strongly dependent on the shape of the pad composites that hold the CeO2 mineral. Fixed abrasive pads with pyramid and pole shapes are available. In this work, three different fixed abrasive pads supplied by 3M corporation were evaluated for STI CMP polish performance using the Obsidian 8200C web format CMP tool. Basic polish characteristics such as planarity (dependence on sub-pad/pattern density), selectivity to topography, oxide dishing and nitride erosion are presented. The FA pads discussed here have been classified as “slow”, “medium” or “fast” depending on blanket oxide removal rate.The slow rate pad had a very high selectivity to topography and very low dishing of the down area oxide. The removal rate of blanket oxide was less than 100 Å/min. The pad was best suited to the polish of isolation trench structures with small, controlled overfill (> 200 Å) across the wafer. A large process window was demonstrated. The removal rate of the “medium” pad also decreased significantly at the onset of planarization with a blanket oxide removal rate of ca. 200 Å/min. Unlike the slow rate pad, the medium rate pad did not provide a suitable overpolish process window required for a manufacturable STI process. It is believed this pad would be a good choice for BPSG polish. In contrast to the slow and medium rate pads, the blanket oxide removal rate of the fast pad was ca. 2000 Å/min with no self-stopping capability at the onset of planarization. The removal rate was extremely center fast, such that it could not be compensated by adjustment of tool parameters. Use of a modified process developed within the DRAM development alliance (DDA) at East Fishkill (IBM/ Infineon) enabled the fast pad to polish deep STI structures that would otherwise be impossible using the slow or medium rate pads.

High Planarization Efficiency and Wide Process Window Using Electro-chemical Mechanical Planarization (EcmpTM)

2005 ◽  
Vol 867 ◽  
Author(s):  
Feng Q Liu ◽  
Liang Chen ◽  
Alain Duboust ◽  
Stan Tsai ◽  
Antoine Manens ◽  
...  
Keyword(s):  
Applied Voltage ◽  
Removal Rate ◽  
Chemical Mechanical Planarization ◽  
Copper Film ◽  
Process Window ◽  
Factors Affecting ◽  
Profile Control ◽  
Planarization Process ◽  
Rate Controlled ◽  
Electrochemical Removal

AbstractEcmpTM is a revolutionary planarization technology uniquely combining removal rate controlled by charge with superior planarization efficiency in the near no shear regime. In addition, the electrochemical removal mechanism has excellent within-wafer profile control. Multiple electrical zones configuration combined with a precise end-point control by electric charge, make it more predictable to control the remaining thickness and profile of copper film. The factors affecting the planarization such as the concentration and the efficiency of the inhibitors will be discussed in this paper. Meanwhile a planarization mechanism for Ecmp will be proposed to match the high planarization efficiency. The effects of applied voltage on removal rate and planarization efficiency will be presented in this paper. The electrical feature allows Ecmp to be a planarization process with removal rate independent of down force, enabling a wide removal rate window based on applied voltage.

Preparation and Evaluation of Hydrophilic Fixed Abrasive Pad

2010 ◽  
Vol 431-432 ◽  
pp. 17-20 ◽  
Author(s):  
Yong Wei Zhu ◽  
Jun Li ◽  
Jun Wang ◽  
Kui Lin
Keyword(s):  
Surface Roughness ◽  
Material Removal Rate ◽  
Material Removal ◽  
Removal Rate ◽  
Urethane Acrylate ◽  
Swelling Ratio ◽  
Pencil Hardness ◽  
Fixed Abrasive Pad ◽  
Preparation And Evaluation ◽  
Fixed Abrasive

The swelling ratio and the pencil hardness of pad were introduced to evaluate the properties of hydrophilic fixed abrasive (FA) pad. The effect of pad composition on its swelling ratio and pencil hardness was studied. Results show that the swelling ratio increases with the rise of content of Trimethylopropane Triacrylate (TMPTA) and Urethane Acrylate (PUA) and the pad gets harder while there is more TMPTA and less PUA. Results also show that a low swelling ratio corresponds to a high material removal rate (MRR), and a low wet pencil hardness to a low surface roughness in each group.

Wafer Scale Modeling and Control for Yield Improvement in Wafer Planarization

2002 ◽  
Author(s):  
Sutee Eamkajornsiri ◽  
Ranga Narayanaswami ◽  
Abhijit Chandra
Keyword(s):  
Material Removal Rate ◽  
Integrated Circuit ◽  
Material Removal ◽  
Large Scale ◽  
Removal Rate ◽  
Control Strategies ◽  
Elastic Half Space ◽  
Modeling And Control ◽  
Planarization Process ◽  
Curvature Control

Chemical mechanical polishing (CMP) is a planarization process that produces high quality surfaces both locally and globally. It is one of the key process steps during the fabrication of very large scale integrated (VLSI) chips in integrated circuit (IC) manufacturing. CMP consists of a chemical process and a mechanical process being performed together to reduce height variation across a wafer. High and reliable wafer yield, which is dependent upon uniformity of the material removal rate across the entire wafer, is of critical importance in the CMP process. In this paper, the variations in material removal rate (MRR) variation across the wafer are analytically modeled assumimg a rigid wafer and a flexible polishing pad. The wafer pad contact is modeled as the indentation of a rigid indenter on an elastic half-space. Load and curvature control strategies are investigated for improving the wafer yield. The notion of curvature control is entirely new and has not been addressed in the literature. The control strategy is based on minimizing a moment function that represents the wafer curvature and the height of the oxide layer left for material removal. Simulation results indicate that curvature control can improve wafer yield significantly, and is more effective than just the load control.

Study on Fixed Abrasive Lapping Hard and Brittle Materials with Brazed Micro Powder Diamond Disk

2013 ◽  
Vol 589-590 ◽  
pp. 451-456 ◽  
Author(s):  
Quan Cheng Li ◽  
Jian Yun Shen ◽  
Cong Fu Fang ◽  
Xi Peng Xu
Keyword(s):  
Surface Morphology ◽  
Silicon Wafer ◽  
Removal Rate ◽  
Brittle Materials ◽  
Alumina Ceramic ◽  
Diamond Disk ◽  
Hard And Brittle Materials ◽  
Fixed Abrasive

In this study, two different arrangement lapping disks fixed with brazed diamond pellets were used to lap silicon wafer and alumina ceramic. The effects of the surface morphology, roughness, and removal rate of workpiece caused by lapping pressure, lapping time, workpiece velocity, and disc arrangement were operated with serials experiments. The results of the researches provided guidance for fixed abrasive lapping of hard and brittle materials with the brazed micro powder diamond disk.

New Approaches for Formation of Ultra-Thin PtSi Layers for Infrared Applications

1998 ◽  
Vol 514 ◽  
Author(s):  
Ricardo A. Donaton ◽  
Sing Jin ◽  
Hugo Bender ◽  
Maxim Zagrebnov ◽  
Kris Baert ◽  
...  
Keyword(s):  
Schottky Barrier ◽  
Infrared Detector ◽  
High Vacuum ◽  
Deposition Process ◽  
Critical Issue ◽  
Device Fabrication ◽  
Thin Layers ◽  
Process Window ◽  
Detector Performance ◽  
Silicide Layer

ABSTRACTPtSi is one of the most used silicides in infrared Schottky barrier detectors due to its low Schottky barrier to p-type Si ( Øb ∼ 0.23 eV). Control of the thickness and uniformity of the silicide layer is fundamental for a good infrared detector performance, since the silicide thickness has to be in the range of 3 to 8 nm. Such thin layers are usually made by evaporation of Pt followed by a furnace annealing. We will show different approaches for fabrication of utra-thin PtSi layers. In all of the processes, high-vacuum sputtering is used for Pt deposition and the silicidation is performed in a rapid thermal annealing system. Smooth and uniform Pt Si layers down to 3 nm thick are formed in this way. It will be shown that the controllability of the thickness during sputter deposition is not a critical issue and the deposition process has a large process window. Moreover, when taking an optimal approach, a large process window can also be found for the RTA step. The implementation of these approaches for device fabrication and some electrial results of diodes made with them will also be presented.

A Fundamental Investigation on Ultrasonic Assisted Fixed Abrasive CMP (UF-CMP) of Silicon Wafer

2014 ◽  
Vol 983 ◽  
pp. 208-213 ◽  
Author(s):  
Yong Bo Wu ◽  
Li Jun Wang
Keyword(s):  
Surface Quality ◽  
Silicon Wafer ◽  
Removal Rate ◽  
High Profile ◽  
Work Surface ◽  
Ultrasonic Assisted ◽  
Polishing Efficiency ◽  
Profile Accuracy ◽  
Abrasive Process ◽  
Fixed Abrasive

Chemical mechanical polishing (CMP) is often employed to obtain a super smooth work-surface of a silicon wafer. However, as a conventional CMP is a loose abrasive process, it is hard to achieve the high profile accuracy and lots of slurry must be supplied during CMP operations. As an alternate solution, a fixed abrasive CMP process can offer better geometrical accuracy and discharges less waste disposal. In this paper, in order to enhance the polishing efficiency and improve the work-surface quality, a novel ultrasonic assisted fixed abrasive CMP (UF-CMP) is proposed and the fundamental machining characteristics of the UF-CMP of a silicon wafer is investigated experimentally. The results show that with the ultrasonic assistance, the material removal rate (MRR) is increased, and the surface quality is improved.

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