Dielectric Material Options for Integrated Capacitors

Abstract

Document VersionPublisher's PDF, also known as Version of Record (includes final page, issue and volume numbers) Please check the document version of this publication:• A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication Citation for published version (APA):Ruhl, G., Lehnert, W., Lukosius, M., Wenger, C., Baristiran Kaynak, C., Blomberg, T., ... Rushworth, S. A. (2014). Dielectric material options for integrated capacitors. ECS Journal of Solid State Science and Technology, 3(8), N120-N125. DOI: 10.1149/2.0101408jss General rightsCopyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.Download date: 11. May. 2018 Science and Technology, 3 (8) N120-N125 (2014) 2162-8769/2014/3(8) Future MIM capacitor generations will require significantly increased specific capacitances by utilization of high-k dielectric materials. In order to achieve high capacitance per chip area, these dielectrics have to be deposited in three-dimensional capacitor structures by ALD or AVD (atomic vapor deposition) process techniques. In this study eight dielectric materials, which can be deposited by these techniques and exhibit the potential to reach k-values of over 50 were identified, prepared and characterized as single films and stacked film systems. To primarily focus on a material comparison, preliminary processes were used for film deposition on planar test devices. Measuring leakage current density versus the dielectric constant k shows that at low voltages (≤1 V) dielectrics with k-values up to 100 satisfy the typical leakage current density specification of <10 −7 A/cm 2 for MIM capacitors. At higher voltages (3 V) this specification is only fulfilled for dielectrics with k-values below 45. As a consequence, the maximum achievable capacitance gain by introducing high-k dielect...

Interdependence of piezoelectric coefficient and film thickness in LiTaO3 cantilevers

“…A lower permittivity value is required to use the device for energy harvesting applications; however, the relative permittivity of these polycrystalline LiTaO 3 films is higher than those of single crystal 44 . Figure 5B summarizes the leakage current of LiTaO 3 cantilevers obtained by applying an electric field of up to 12 V bottom and top electrode of the cantilever, which decreased with film thickness; the resulting current was measured and leakage current density (J) was found to be 4.651 × 10 −4 , 4.651 × 10 −5 , and 4.651 × 10 −7 A/m 2 for the LT samples 2, 4, and 6, respectively, which correlates well with published reports 45 . A thicker piezoelectric film has a lower leakage current due to different grain size of the material as the number of layers increases 46 .…”

“…44 leakage current density (J) was found to be 4.651 × 10 −4 , 4.651 × 10 −5 , and 4.651 × 10 −7 A/m 2 for the LT samples 2, 4, and 6, respectively, which correlates well with published reports. 45 A thicker piezoelectric film has a lower leakage current due to different grain size of the material as the number of layers increases. 46 A low leakage current ensures efficient charge generation for the piezoelectric applications, as resulting charges dissipate slower.…”

Review—Investigation and Review of the Thermal, Mechanical, Electrical, Optical, and Structural Properties of Atomic Layer Deposited High-kDielectrics: Beryllium Oxide, Aluminum Oxide, Hafnium Oxide, and Aluminum Nitride

“…[1][2][3][4][5][6][7][8] Many of these same high-k materials have found additional applications in future non-CMOS logic and memory storage products such as solid-state electrolytes in resistive switching devices, 9,10 tunnel barriers in spin-transport devices, 11 and as a ferroelectric in magnetoelectric devices. 12,13 They have also enabled significant performance gains in a wide variety of energy storage, 14,15 photovoltaic, 16,17 optoelectronic, 18 high-frequency, 19,20 high-power, 21 and high-temperature devices. 22 Due to exceptional thickness control and uniformity, atomic layer deposition (ALD) has become the preferred method for depositing most high-k dielectric materials in micro-/nano-electronic applications.…”

“…Al 2 O 3 was one of the earliest candidates considered to replace SiO 2 as the CMOS gate dielectric, but has since been supplanted by HfO 2 primarily due to its higher dielectric constant (Al 2 O 3 k = 8-10 vs. HfO 2 k ∼ 25). 2 However, due to large band gaps [2][3][4] and favorable valence and conduction band alignments, 4,[67][68][69] Al 2 O 3 and HfO 2 both continue to play an important role as highk dielectrics in three-dimensional (3D) memory and energy storage structures, 14,20 RF blocking/decoupling capacitors, 15,20 high-mobility and tunnel field effect III-V devices, [70][71][72] high-power, high-frequency, and high-temperature III-N devices, 21,22,73,74 and 2D transition metal dichalcogenide CMOS devices. [75][76][77] In addition, the high thermodynamic stability 29 and atomic/mass density 28 of Al 2 O 3 has enabled it to serve as an optical coating material, 30 surface passivation layer in Si solar cells, 16,78 hermetic encapsulation layer for OLED and packaging applications, 34,35 metal 36 and gas 27,31,32 diffusion barrier in microelectronic applications, and as a corrosion and stiction protection layer in NEM devices.…”

Investigation on Multifunctional Properties of (Pb0.92La0.08) (Zr0.55Ti0.45)O3 Relaxor Ferroelectric Thin Film for Energy‐Harvesting and Storage Applications

“…[ 63 ] These two different electrodes introduce different injection and collection efficiency of the electrodes. [ 73 ] At near room temperature (293.15 K), a leakage current density of around 0.3 μA cm −2 is observed at a measurement voltage of 5 V. With an increase in the applied electric field, the trapped defects in the material acquire enough energy to move from their defect energy level to the conduction band, contributing to higher leakage current. A linear dependence of leakage current with electric field is initially noted at lower electric field regions, which is attributed to the Ohmic conduction mechanism in the film.…”