Process‐induced mechanical stress in isolation structures studied by micro‐Raman spectroscopy

1993 ◽  
Vol 74 (7) ◽  
pp. 4490-4500 ◽  
Author(s):  
I. De Wolf ◽  
H. Norström ◽  
H. E. Maes
Keyword(s):  
Raman Spectroscopy ◽  
Mechanical Stress ◽  
Micro Raman Spectroscopy

Micro-Raman Spectroscopy Evaluation of the Local Mechanical Stress in Shallow Trench Isolation CMOS Structures: Correlation with Defect Generation and Diode Leakage

1998 ◽  
Author(s):  
I. De Wolf ◽  
G. Groeseneken ◽  
H.E. Maes ◽  
M. Bolt ◽  
K. Barla ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Mechanical Stress ◽  
Defect Formation ◽  
Active Area ◽  
Wet Oxidation ◽  
Leakage Currents ◽  
Shallow Trench Isolation ◽  
Micro Raman Spectroscopy ◽  
Silicon Devices ◽  
Trench Isolation

Abstract It is shown, using micro-Raman spectroscopy, that Shallow Trench Isolation introduces high stresses in the active area of silicon devices when wet oxidation steps are used. These stresses result in defect formation in the active area, leading to high diode leakage currents. The stress levels are highest near the outer edges of line structures and at square structures. They also increase with decreasing active area dimensions.

Variation of Local Mechanical Stress During the Different Processing Steps of Ic-Isolation: a Micro-Raman Spectroscopy Study

1993 ◽  
Vol 308 ◽  
Author(s):  
Ingrid De Wolf ◽  
Herman E. Maes ◽  
Hans Norström
Keyword(s):  
Raman Spectroscopy ◽  
Integrated Circuits ◽  
Mechanical Stress ◽  
Local Variation ◽  
Micro Raman Spectroscopy ◽  
Induced Stress ◽  
Last Stage ◽  
Edge Force ◽  
Field Oxide ◽  
Processing Steps

ABSTRACTLocal mechanical stress introduced in the silicon substrate during the successive steps of poly-buffered local isolation of MOS integrated circuits is studied with micro-Raman spectroscopy. It is shown that the magnitude and the local variation of the stress is highly affected by the different processing steps. After deposition of the nitride mask, the stress can be described as caused by an edge-force. Field oxidation reduces the mask-induced stress but introduces thermal stress from the field oxide. Also the formation of the bird's beak gives rise to additional local tensile stress, especially at the tip of the bird's beak. Removal of the nitride mask results in a partial relaxation: the stress caused by the bird's beak relaxes. In this last stage of the isolation process, the stress image is mostly determined by the field oxide.

Stress in Silicon Due to the Formation of Self Aligned Poly-CoSi2 Lines Studied by Micro-Raman Spectroscopy

1995 ◽  
Vol 402 ◽  
Author(s):  
D. J. Howard ◽  
I. De Wolf ◽  
H. Bender ◽  
K. Maex
Keyword(s):  
Raman Spectroscopy ◽  
Mechanical Stress ◽  
Cross Section ◽  
Line Width ◽  
Silicon Substrate ◽  
Theoretical Modeling ◽  
Micro Raman Spectroscopy ◽  
Thermal Oxide ◽  
Stress Profiles ◽  
Cobalt Silicides

AbstractThe application of CoSi2 in ever shrinking Si CMOS source-drain technologies demands a better knowledge of the states of stress caused by the formation of cobalt-silicides in Si. In this study the variation in local mechanical stress in the silicon substrate near arrays of polycrystalline cobalt-silicide lines was investigated by micro-Raman spectroscopy. The lines were formed by annealing Co sputtered in windows in lithographically patterned, thermal oxide coated Si wafers. The CoSi2 lines varied in width from ˜0.25 to 5.0μ, in number from 2 to 7, and in thickness from ˜ 10 to 230nm. The spacing between lines was 1 and 3 times the line width.Trends in the Si stress between CoSi2 lines are described as a function of line width and line thickness. From the stress measured in the Si, information is obtained about the stress in the CoSi2 lines. In addition, the Si stress due to lines of primarily CoSi phase (monosilicide) is compared with the Si stress due to polycrystalline-CoSi2 (disilicide) lines.Cross section TEM and SEM micrographs of the CoSix line morphologies are used to aid the description of the resulting stress profiles. Some theoretical modeling of the stress in the Si due to the CoSix lines is presented for comparison with the micro-Raman spectroscopy results.

Experimental validation of mechanical stress models by micro-Raman spectroscopy

1996 ◽  
Vol 36 (11-12) ◽  
pp. 1751-1754 ◽  
Author(s):  
I. De Wolf ◽  
G. Pozzat ◽  
K. Pinardi ◽  
D.J. Howard ◽  
M. Ignat ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Mechanical Stress ◽  
Experimental Validation ◽  
Micro Raman Spectroscopy ◽  
Stress Models

The Influence of Mechanical Stress on Hot-Carrier Degradation in Mosfet's

1993 ◽  
Vol 309 ◽  
Author(s):  
Ingrid De Wolf ◽  
Rudi Bellens ◽  
Guido Groeseneken ◽  
Herman E. Maes
Keyword(s):  
Raman Spectroscopy ◽  
Tensile Stress ◽  
Mechanical Stress ◽  
Interface Trap ◽  
Degradation Behaviour ◽  
Hot Carrier ◽  
Stress Measurements ◽  
Micro Raman Spectroscopy ◽  
Hot Carrier Degradation

AbstractNon-uniform hot-carrier degradation in n-channel polycide-gate MOSFET's with different thicknesses of the poly-Si film, and in p-channel polycide-gate MOSFET's with TiSi2- or CoSi2-gate-silicide, is studied. The n-MOSFET's with the thinnest poly-Si film, show an increased interface trap generation, while the influence of the gate-silicide material on the degradation behaviour of the p-MOSFET's is found to be very small. The results are evaluated in terms of the effect of mechanical stress on the degradation characteristics: favourable for compressive mechanical stress and unfavourable for tensile stress. A correlation with stress measurements by micro-Raman spectroscopy is made.

Phase and Mechanical Stress in and Surrounding Tisi2 and Cosi2 Lines Studied by Micro-Raman Spectroscopy

1996 ◽  
Vol 427 ◽  
Author(s):  
I. De Wolf ◽  
D. J. Howard ◽  
K. Maex ◽  
H. E. Maes
Keyword(s):  
Raman Spectroscopy ◽  
Mechanical Stress ◽  
Line Width ◽  
Silicon Substrate ◽  
Local Information ◽  
Stress Model ◽  
Micro Raman Spectroscopy ◽  
Stress Components ◽  
Line Spacing ◽  
Simple Stress

AbstractThe local mechanical stress induced in a silicon substrate by silicide lines (CoSi2, CoSi, C49 and C54 TiSi2) with different thicknesses, widths and spacings is studied using micro-Raman spectroscopy. The results show that the stress becomes larger with increasing line thickness and decreasing line spacing. For the different silicides, the stress increases according to: CoSi < CoSi2 < C49 TiSi2 < C54 TiSi2. By fitting a simple stress model to the Raman data, quantitative values for the stress components can be determined. The dependence of the TiSi2 phase on thickness and line width is studied for the same samples. These studies show that micro-Raman spectroscopy can provide local information (μm resolution) on the TiSi2 phase.

The Influence of Mechanical Stress on Hot-Carrier Degradation in Mosfet'S

1993 ◽  
Vol 308 ◽  
Author(s):  
Ingrid De Wolf ◽  
Rudi bellens ◽  
Guido Groeseneken ◽  
Herman E. Maes
Keyword(s):  
Raman Spectroscopy ◽  
Tensile Stress ◽  
Mechanical Stress ◽  
Interface Trap ◽  
Degradation Behaviour ◽  
Hot Carrier ◽  
Stress Measurements ◽  
Micro Raman Spectroscopy ◽  
Hot Carrier Degradation

ABSTRACTNon-uniform hot-carrier degradation in n-channel polycide-gate MOSFET's with different thicknesses of the poly-Si film, and in p-channel polycide-gate MOSFET's with TiSi2- or CoSi2-gate-silicide, is studied. The n-MOSFET's with the thinnest poly-Si film, show an increased interface trap generation, while the influence of the gate-silicide material on the degradation behaviour of the p-MOSFET's is found to be very small. The results are evaluated in terms of the effect of mechanical stress on the degradation characteristics: favourable for compressive mechanical stress and unfavourable for tensile stress. A correlation with stress measurements by micro-Raman spectroscopy is made.

Sign in / Sign up

Export Citation Format

Share Document