Endpoint detection for CMP

Bibby, T.; Holland, Karey

doi:10.1007/s11664-998-0140-1

Cited by 41 publications

(22 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…113 Introduction of these or other new materials will require new slurries as well as reoptimization of the entire process recipe. For example, these new materials complicate the P5038 ECS Journal of Solid State Science and Technology, 4 (11) P5029-P5039 (2015) end point detection methodology, 114 especially if the optical properties of the materials or the coefficient of friction are very different. Also, for materials such as silicon oxynitride used with an underlying silicon nitride stop layer, the difference in optical properties may not be sufficiently large for the optical method to identify the end point.…”

Section: Current Challengesmentioning

confidence: 99%

Shallow Trench Isolation Chemical Mechanical Planarization: A Review

Ramanathan

Dandu

Babu

2015

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

Electrical isolation of the billion or so active components in each integrated device is achieved using shallow trench isolation (STI) which requires chemical mechanical planarization (CMP) involving silicon dioxide removal at a high rate and stopping on an underlying silicon nitride film. Several colloidal slurries with various additives can yield the desired high rate selectivity between the oxide and nitride films during CMP while maintaining an acceptably low nitride rate. Here, many of such high selectivity STI CMP slurries described in the literature are reviewed along with the characteristics of the colloidal dispersions like the abrasives, additives, the interactions between them and with the films being planarized and the associated pH range in which the high selectivity is observed. The mechanisms proposed to explain the high reactivity of ceria with oxide, the role of additives in suppressing the nitride removal rate and resulting high selectivity are discussed. Reduction of a multitude of defects in post-CMP processed STI structures still remains an important challenge, especially as the feature sizes continue to shrink. Chemical mechanical planarization (CMP) is one of the important enabling processes in facilitating multilevel metallization (in some cases reaching up to 14 levels) and incorporation of novel gate and channel materials at the component level in modern semiconductor device manufacturing where its use has become widespread and ubiquitous.1-6 Here, we review recent advances and remaining challenges in one specific application of CMP, the shallow trench isolation (STI) process. STI is a method of electrically isolating active areas using trenches created in the Si substrate around the active elements and filling it with an insulating dielectric, such as silicon dioxide or silicon oxy-nitride or silicon carbonitride.7-11 Process details of the STI structures are available in numerous publications. There are a multitude of techniques available for oxide deposition and even though the resulting oxides have very different properties, for simplicity we do not distinguish between them in this review. For completeness and ease of reference, a schematic representation of the STI process is given in Figure 1. While the trenches are being filled, silicon dioxide also deposits over unwanted areas on the entire wafer (since selective deposition in trenches only is not possible) creating an uneven topography. The excess and unwanted oxide has to be completely removed and CMP has proven to be the only viable and robust global and local planarization capable process technology.Here, as shown in Figure 1, presence of a very thin silicon nitride stop layer (deposited on another thin pad oxide layer to control film stress) is an essential and integral part of the process. This nitride stop layer prevents any damage during planarization to the all-important epitaxially grown surface underneath and is itself removed by a wet etch process subsequent to the overburden oxide removal. Since the integrity of the...

show abstract

Section: Current Challengesmentioning

confidence: 99%

Shallow Trench Isolation Chemical Mechanical Planarization: A Review

Ramanathan

Dandu

Babu

2015

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…They fall into categories such as thermal, torque motor current, chemical, electrical or electrochemical, optical, and vibration. For an earlier review on endpoint detection for CMP see Bibby, et al 2 For reference, we have summarized list of relevant U.S. patents on in-line monitoring techniques for CMP given in Table 1 at the end of this section.…”

Section: Monitoring Techniquesmentioning

confidence: 99%

<title>In-line monitoring of chemical-mechanical polishing processes</title>

Hetherington

Stein

1999

SPIE Proceedings

View full text Add to dashboard Cite

show abstract

“…However, due to the nature of the ILD oxide, there is no stopping layer and hence lacks an effective endpoint detection technology at CMP. It has been historically considered a "blind" CMP process, presenting tremendous challenges to achieving across wafer uniformity and defect control [2]. With semiconductor process technology advances to even smaller geometry, the within wafer nonuniformity issue of ILD oxide CMP, especially at the very edge of a wafer, becomes a top device yield killer for high volume IC manufacturing.…”

Section: Introductionmentioning

confidence: 99%

“…With semiconductor process technology advances to even smaller geometry, the within wafer nonuniformity issue of ILD oxide CMP, especially at the very edge of a wafer, becomes a top device yield killer for high volume IC manufacturing. Advanced process control technologies and hardware, such as in-situ polishing pressure control using multi-zone polishing heads and optical endpoint systems, have been developed for ILD oxide CMP process control for 0.09 µm technology and beyond [2]. However, current transistor number multiplication and geometry miniaturization to enable higher density and higher speed devices have outpaced semiconductor hardware advancements and breakthroughs.…”

Section: Introductionmentioning

confidence: 99%

A novel method to address ILD CMP non-uniformity issue for advanced memory device integration

Wei

McDaniel

Jindal

et al. 2012

2012 IEEE Workshop on Microelectronics and Electron Devices

View full text Add to dashboard Cite

CMP non-uniformity has been an increasingly critical issue that needs to be addressed as memory device geometries continue to shrink. This issue is more prominent for ILD oxide CMP due to its poor controllability as compared to other CMP processes that can rely on stopping layers for effective endpoint detections and non-uniformity control. In this paper, we propose a novel approach to address the ILD oxide CMP non-uniformity issue by introducing a dual film polish concept. Experimental results show that this approach improves wafer non-uniformity and reduces scratches. Final device probe yield suggests that the approach is valid. A rate model is also proposed to elucidate the dual film CMP process.

show abstract

Endpoint detection for CMP

Cited by 41 publications

References 8 publications

Shallow Trench Isolation Chemical Mechanical Planarization: A Review

Shallow Trench Isolation Chemical Mechanical Planarization: A Review

<title>In-line monitoring of chemical-mechanical polishing processes</title>

A novel method to address ILD CMP non-uniformity issue for advanced memory device integration

Contact Info

Product

Resources

About