Ultraviolet radiation effects on paramagnetic defects in low-κ dielectrics for ultralarge scale integrated circuit interconnects

Bittel, Brad C.; Lenahan, Patrick M.; King, Sean W.

doi:10.1063/1.3478235

Cited by 28 publications

(23 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Increasing defect densities and leakage currents after UV light irradiation are also discussed in other literature reports. 42 Sinha et al 43 suggested that photon irradiation produces trapped charges inside the low-k material, where such charge accumulation leads to potential reliability problems.…”

Section: Reliability After Integrationmentioning

confidence: 99%

Electrical Reliability Challenges of Advanced Low-k Dielectrics

Baklanov

et al. 2014

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

We review the latest studies that address the fundamental understanding of low-k dielectric electrical properties and reliability. We focus on the results discussing the nature of process induced defects, leakage currents and breakdown behavior, as they are important factors to reveal material modification and damage. Issues related to the use of porogen based PECVD techniques during dielectric deposition are discussed, where we focus on the selection of matrix and porogen precursors and on the improvements related to post-deposition treatments. During damascene integration, low-k dielectrics are subjected to several processes that induce material damage, where we review recent learning about plasma exposure, barrier deposition and chemical mechanical polishing. In order to have a successful implementation of advanced ultralow-k films in back-end-of-line interconnects, we argue that more research efforts are needed with respect to its material development, integration and reliability and make some proposals for future work. The development and integration of reliable low-k materials is a key challenge for next generation interconnect technologies. Driven by the requirement of performance increase, highly porous low-k dielectrics are incorporated in deeply scaled back-end-of-line (BEOL) interconnects. In general, there are three important concerns during the study of low-k dielectric electrical properties and reliability: a) the k-value of the dielectric after integration should maintain relatively unchanged, b) the leakage current of the dielectric between metal lines should be low, and c) the time dependent dielectric breakdown (TDDB) failure time of the integrated BEOL structure at operating conditions should meet its specifications. 1Porous SiOCH low-k dielectrics deposited by plasma enhanced chemical vapor deposition (PECVD) techniques are the dominant choice for k>2.2 film depositions and are also potential candidates for ultralow-k (k<2.2) dielectric applications.2 In the past years, significant efforts have been spent to understand their material properties and integration challenges. The bond structures of low-k dielectrics is complex due to the non-equilibrium nature of the PECVD technique.

show abstract

Section: Reliability After Integrationmentioning

confidence: 99%

Electrical Reliability Challenges of Advanced Low-k Dielectrics

Baklanov

et al. 2014

ECS J. Solid State Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…[244][245][246] Additional studies have shown that UV curing can also result in an increase in paramagnetic defect densities and leakage currents. 247 Integrated requirements.-Cu/metal diffusion resistance.-An obvious integrated requirement for any dielectric diffusion barrier / metal capping layer is to prevent diffusion of the metal wire into the surrounding ILD. The presence of metal contamination in the ILD has been attributed to a number of reliability issues 248 such as increased leakage currents, [249][250][251] decreased TDDB lifetime [252][253][254][255][256][257][258] and shifts in CMOS device performance.…”

Section: -122mentioning

confidence: 99%

Dielectric Barrier, Etch Stop, and Metal Capping Materials for State of the Art and beyond Metal Interconnects

King

2014

ECS J. Solid State Sci. Technol.

133

115

View full text Add to dashboard Cite

Over the past decade, the primary focus for improving the performance of nano-electronic metal interconnect structures has been to reduce the impact of resistance-capacitance (RC) delays via utilizing insulating dielectrics with ever lower values of dielectric permittivity. The integration and implementation of such low dielectric constant (i.e. low-k) materials has been fraught with numerous challenges. For intermetal and interlayer (ILD) low-k dielectrics, these challenges have been largely associated to integration with metal interconnect fabrication processes and well documented and reviewed in the literature. Although equally important, less attention has been given to other low-k dielectrics utilized in metal interconnect structures that are commonly referred to as low-k dielectric barriers (DB), etch stops (ES), and/or Cu capping layers (CCL). These materials present numerous challenges as well for integration into metal interconnect fabrication processes. However, they also have more stringent integrated functionality requirements relative to low-k ILD materials that serve only a basic purpose of electrically isolating adjacent metal lines. In this article, we review the integration challenges and associated integrated functionality requirements for low-k DB/ES/CCL materials with a focus on the current status and future direction needed for these materials to facilitate both Moore's law (i.e. More Moore) and More than Moore scaling.

show abstract

“…3 It has been shown that the defect bonding structures in the dielectric layers, as well as potential copper contamination due to the structure of the interconnects, are responsible for these large leakage currents. [4][5][6][7] It was found that defects in the dielectric layers lead to intrinsic leakage currents without the presence of metal layers. 5 Hence, an investigation of the nature of the defects in SiCOH along with methods to reduce them is critical for industrial application of these materials.…”

mentioning

confidence: 99%

“…[4][5][6][7] It was found that defects in the dielectric layers lead to intrinsic leakage currents without the presence of metal layers. 5 Hence, an investigation of the nature of the defects in SiCOH along with methods to reduce them is critical for industrial application of these materials. 8 For high-k dielectrics, specific processing steps were undertaken to exclusively modify each bonding structure of concern so that the resulting changes in defect concentration, as measured by electron spin resonance ͑ESR͒, can be directly linked to changes to specific chemical bonds.…”

mentioning

confidence: 99%

“…9 However, the corresponding bonding structures of the defects in SiCOH have not yet been determined. 5 Now, the ability to deposit SiCOH on high-resistivity 10 substrates makes it possible to quantify the defect concentrations in a similar way. 6 In this letter, we extend this work to explore the nature of the defects in low-k dielectrics, such as SiCOH and search for potential methods to reduce the defect concentrations.…”

mentioning

confidence: 99%

See 1 more Smart Citation