Single-Crystalline and Bamboo Al Lines Fabricated by Graphoepitaxy: Microstructure and 1/f Noise Measurements

1996 ◽  
Vol 428 ◽  
Author(s):  
Marc J.C. Van Den Homberg ◽  
A. H. Verbruggen ◽  
P. F. A. Alkemade ◽  
S. Radelaar
Keyword(s):  
Integrated Circuits ◽  
Grain Boundaries ◽  
Low Noise ◽  
Dc Magnetron Sputtering ◽  
Rapid Thermal Anneal ◽  
Single Crystalline ◽  
Noise Measurements ◽  
Scaling Down ◽  
Sputter Deposited

AbstractThe continuing scaling-down of integrated circuits leads to increased metallization reliability problems, especially electromigration. We used 1/f noise measurements to study the relation between electromigration and microstructure. These measurements are very sensitive to the microstructural attributes, such as grain boundaries and dislocations. Al lines were grown by graphoepitaxy: First, a pure Al film was grown by dc magnetron sputtering on a groove pattern etched into a SiO2 substrate. The growth was then followed by an in situ rapid thermal anneal that resulted in a complete filling of the grooves with Al. These Al lines were carefully characterized with SEM and Backscatter Kikuchi Diffraction. Depending on the presence of a temperature gradient during the anneal, the lines were either nearly single-crystalline or bamboo with one grain per ∼ 3 μm. The resistivity was ∼ 2.8 μΩcm, only slightly higher than for bulk Al. We measured the 1/f noise with the two-channel ac technique at RT. We found in both bamboo as well as the single-crystalline lines a very low noise intensity; a factor two lower than in conventionally sputter deposited and annealed Al lines. No clear difference between the noise spectra of the bamboo and the single-crystalline lines was observed. We concluded that grain boundaries are not the only contributor to 1/f noise; other types of defects must play a role as well.

scholarly journals Optimization of spaceflight millimeter-wave impedance matching networks using laser trimming

2021 ◽  
pp. 1-7
Author(s):  
K. Parow-Souchon ◽  
D. Cuadrado-Calle ◽  
S. Rea ◽  
M. Henry ◽  
M. Merritt ◽  
...  
Keyword(s):  
Integrated Circuits ◽  
Millimeter Wave ◽  
Impedance Matching ◽  
Wave Impedance ◽  
Low Noise ◽  
Device Performance ◽  
Interface Circuits ◽  
Interface Circuit ◽  
Noise Amplifier

Abstract Realizing packaged state-of-the-art performance of monolithic microwave integrated circuits (MMICs) operating at millimeter wavelengths presents significant challenges in terms of electrical interface circuitry and physical construction. For instance, even with the aid of modern electromagnetic simulation tools, modeling the interaction between the MMIC and its package embedding circuit can lack the necessary precision to achieve optimum device performance. Physical implementation also introduces inaccuracies and requires iterative interface component substitution that can produce variable results, is invasive and risks damaging the MMIC. This paper describes a novel method for in situ optimization of packaged millimeter-wave devices using a pulsed ultraviolet laser to remove pre-selected areas of interface circuit metallization. The method was successfully demonstrated through the optimization of a 183 GHz low noise amplifier destined for use on the MetOp-SG meteorological satellite series. An improvement in amplifier output return loss from an average of 12.9 dB to 22.7 dB was achieved across an operational frequency range of 175–191 GHz and the improved circuit reproduced. We believe that our in situ tuning technique can be applied more widely to planar millimeter-wave interface circuits that are critical in achieving optimum device performance.

Electrical and structural properties of ultrathin polycrystalline and epitaxial TiN films grown by reactive dc magnetron sputtering

2009 ◽  
Vol 1156 ◽  
Author(s):  
Fridrik Magnus ◽  
Arni Sigurdur Ingason ◽  
Sveinn Olafsson ◽  
Jon Tomas Gudmundsson
Keyword(s):  
Magnetron Sputtering ◽  
Structural Properties ◽  
Dc Magnetron Sputtering ◽  
Single Crystalline ◽  
Tin Films ◽  
X Ray

AbstractUltrathin TiN films were grown by reactive dc magnetron sputtering on amorphous SiO2 substrates and single-crystalline MgO substrates at 600°C. The resistance of the films was monitored in-situ during growth to determine the coalescence and continuity thicknesses. TiN films grown on SiO2 are polycrystalline and have coalescence and continuity thicknesses of 8 Å and 19 Å, respectively. TiN films grow epitaxially on the MgO substrates and the coalescence thickness is 2 Å and the thickness where the film becomes continuous cannot be resolved from the coalescence thickness. X-ray reflection measurements indicate a significantly higher density and lower roughness of the epitaxial TiN films.

Electromigration and 1/ƒ Noise in Single-Crystalline, Bamboo and Polycrystalline Al Lines

1997 ◽  
Vol 473 ◽  
Author(s):  
Marc J.C. Van Den Homberg ◽  
P.F.A. Alkemade ◽  
A. H. Verbruggen ◽  
A. G. Dirks ◽  
E. Ochs ◽  
...  
Keyword(s):  
Activation Energy ◽  
Grain Boundaries ◽  
Single Crystals ◽  
Pipe Diffusion ◽  
Single Crystalline ◽  
Interface Diffusion ◽  
Measured Activation Energy ◽  
Noise Measurements ◽  
Measured Activation ◽  
Groove Pattern

ABSTRACTThe relation between electromigration and microstructure for three types of Al lines with different microstructures has been studied. The lines were made by recrystallization of Al in a SiO2 groove pattern. They were either truly bamboo with grains of on average 3 μm long or distorted (i.e. with dislocations) single-crystals. In addition, conventional, polycrystalline Al lines with grains of on average 230 nm were made. The lines were lifetime-tested (200 °C,j=2, 5 and 8 MA/cm2) and subjected to l/f noise measurements (from 200 to 500 K).The bamboo and single-crystalline Al lines showed the same, although weak, 1/ƒ noise. This observation demonstrates that other mechanisms than thermal motion of atoms at grain boundaries can cause noise. It is suggested that dislocations are the sources for noise in our samples. The measured activation energy (0.8 eV) is in agreement with the activation energy for pipe diffusion along dislocation lines.The lifetime-tests showed significantly higher times to failure for the single-crystalline and bamboo lines as compared to polycrystalline lines. Preliminary results indicate slightly higher lifetimes for the bamboo than for the single-crystalline lines. It is concluded that interface diffusion is the main mechanism for electromigration in truly bamboo or single-crystalline lines. Our measurements demonstrated that dislocations are important in the formation of l/ƒ noise and interfaces in the formation of electromigration damage.

Electromigration and 1/f Noise in Single-Crystalline, Bamboo and Polycrystalline Al Lines

1997 ◽  
Vol 472 ◽  
Author(s):  
Marc J.C. Van Den Homberg ◽  
P.F.A. Alkemade ◽  
A.H. Verbruggen ◽  
A.G. Dirks ◽  
E. Ochs ◽  
...  
Keyword(s):  
Activation Energy ◽  
Grain Boundaries ◽  
Single Crystals ◽  
Pipe Diffusion ◽  
Single Crystalline ◽  
Interface Diffusion ◽  
Measured Activation Energy ◽  
Noise Measurements ◽  
Measured Activation ◽  
Groove Pattern

ABSTRACTThe relation between electromigration and microstracture for three types of Al lines with different microstructures has been studied. The lines were made by recrystallization of Al in a SiO2 groove pattern. They were either truly bamboo with grains of on average 3 μm long or distorted (i.e. with dislocations) single-crystals. In addition, conventional, polycrystalline Al lines with grains of on average 230 nm were made. The lines were lifetime-tested (200 °C,j=2, 5 and 8 MA/cm2) and subjected to 1/f noise measurements (from 200 to 500 K).The bamboo and single-crystalline Al lines showed the same, although weak, 1/f noise. This observation demonstrates that other mechanisms than thermal motion of atoms at grain boundaries can cause noise. It is suggested that dislocations are the sources for noise in our samples. The measured activation energy (0.8 eV) is in agreement with the activation energy for pipe diffusion along dislocation lines.The lifetime-tests showed significantly higher times to failure for the single-crystalline and bamboo lines as compared to polycrystalline lines. Preliminary results indicate slightly higher lifetimes for the bamboo than for the single-crystalline lines. It is concluded that interface diffusion is the main mechanism for electromigration in truly bamboo or single-crystalline lines. Our measurements demonstrated that dislocations are important in the formation of 1/f noise and interfaces in the formation of electromigration damage.

TEM characterization of WSix films

1994 ◽  
Vol 52 ◽  
pp. 848-849
Author(s):  
V. C. Kannan ◽  
S. M. Merchant ◽  
R. B. Irwin ◽  
A. K. Nanda ◽  
M. Sundahl ◽  
...  
Keyword(s):  
Integrated Circuits ◽  
Vapor Deposition ◽  
High Purity ◽  
Physical Vapor Deposition ◽  
Thermal Treatments ◽  
Rapid Thermal Anneal ◽  
Tungsten Silicide ◽  
Tem Characterization ◽  
Metal Silicides

Metal silicides such as WSi2, MoSi2, TiSi2, TaSi2 and CoSi2 have received wide attention in recent years for semiconductor applications in integrated circuits. In this study, we describe the microstructures of WSix films deposited on SiO2 (oxide) and polysilicon (poly) surfaces on Si wafers afterdeposition and rapid thermal anneal (RTA) at several temperatures. The stoichiometry of WSix films was confirmed by Rutherford Backscattering Spectroscopy (RBS). A correlation between the observed microstructure and measured sheet resistance of the films was also obtained.WSix films were deposited by physical vapor deposition (PVD) using magnetron sputteringin a Varian 3180. A high purity tungsten silicide target with a Si:W ratio of 2.85 was used. Films deposited on oxide or poly substrates gave rise to a Si:W ratio of 2.65 as observed by RBS. To simulatethe thermal treatments of subsequent processing procedures, wafers with tungsten silicide films were subjected to RTA (AG Associates Heatpulse 4108) in a N2 ambient for 60 seconds at temperatures ranging from 700° to 1000°C.

Preparation of integrated circuits for TEM electromigration in situ studies

1986 ◽  
Vol 44 ◽  
pp. 882-883
Author(s):  
J. V. Maskowitz ◽  
W. E. Rhoden ◽  
D. R. Kitchen ◽  
R. E. Omlor ◽  
P. F. Lloyd
Keyword(s):  
Integrated Circuits ◽  
Crystallographic Orientation ◽  
Silicon Wafers ◽  
Minimum Size ◽  
Test Vehicle ◽  
In Situ Studies ◽  
Boron Doped ◽  
Doped Silicon ◽  
Drill Holes

The fabrication of the aluminum bridge test vehicle for use in the crystallographic studies of electromigration involves several photolithographic processes, some common, while others quite unique. It is most important to start with a clean wafer of known orientation. The wafers used are 7 mil thick boron doped silicon. The diameter of the wafer is 1.5 inches with a resistivity of 10-20 ohm-cm. The crystallographic orientation is (111).Initial attempts were made to both drill and laser holes in the silicon wafers then back fill with photoresist or mounting wax. A diamond tipped dentist burr was used to successfully drill holes in the wafer. This proved unacceptable in that the perimeter of the hole was cracked and chipped. Additionally, the minimum size hole realizable was > 300 μm. The drilled holes could not be arrayed on the wafer to any extent because the wafer would not stand up to the stress of multiple drilling.

The reaction of amorphous Ni-Nb films with Si in the presence of a native SiO2 layer

1990 ◽  
Vol 48 (4) ◽  
pp. 664-665
Author(s):  
N. Rozhanski ◽  
A. Barg
Keyword(s):  
High Temperature ◽  
Crystallization Temperature ◽  
Diffusion Barriers ◽  
Sio2 Layer ◽  
Si Substrate ◽  
Cross Sectional ◽  
Plan View ◽  
Temperature Range ◽  
Sputter Deposited

Amorphous Ni-Nb alloys are of potential interest as diffusion barriers for high temperature metallization for VLSI. In the present work amorphous Ni-Nb films were sputter deposited on Si(100) and their interaction with a substrate was studied in the temperature range (200-700)°C. The crystallization of films was observed on the plan-view specimens heated in-situ in Philips-400ST microscope. Cross-sectional objects were prepared to study the structure of interfaces.The crystallization temperature of Ni5 0 Ni5 0 and Ni8 0 Nb2 0 films was found to be equal to 675°C and 525°C correspondingly. The crystallization of Ni5 0 Ni5 0 films is followed by the formation of Ni6Nb7 and Ni3Nb nucleus. Ni8 0Nb2 0 films crystallise with the formation of Ni and Ni3Nb crystals. No interaction of both films with Si substrate was observed on plan-view specimens up to 700°C, that is due to the barrier action of the native SiO2 layer.

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