Polysilicon Grain Growth by Rapid Isothermal Annealing

1984 ◽  
Vol 33 ◽  
Author(s):  
R. F. Pinizzotto ◽  
F. Y. Clark ◽  
S. D. S. Malhi ◽  
R. R. Shah
Keyword(s):  
Grain Size ◽  
Integrated Circuits ◽  
Film Thickness ◽  
Grain Growth ◽  
Isothermal Annealing ◽  
Three Dimensional ◽  
Oxide Thickness ◽  
Kinetics Of ◽  
Microstructure Of The Material ◽  
Short Times

ABSTRACTone method of reducing the area occupied by a RAM cell is to stack the p- and n-channel devices on top of one another. This “stacked CMOS” structure is a first step towards three dimensional integration. The simplest approach is to use polysilicon as the substrate for the top transistors. This paper describes the results of grain growth studies of samples annealed by rapid isothermal annealing. The temperature varied from 1100 to 1400°C and the anneal time varied from 10 to 480 seconds. TEM was used to examine the microstructure of the material. The grain growth was found to be film thickness limited, i.e. the final grain size was approximately the same as the initial film thickness. As a result, the kinetics of grain growth cannot be described by a simple logarithmic time law. There also is a velocity dependent drag contribution to the growth kinetics that implies impurities play an important role. The interlevel oxide thickness affects grain growth. Thicker oxides lead to faster growth, probably by reducing the heat flow to the silicon substrate. A capping layer was found to have no effect on the grain size. The above results indicate that it is possible to obtain large grains in short times using isothermal annealing. This process may be useful for fabricating stacked polysilicon layers in three-dimensional integrated circuits.

scholarly journals Experimental Study on the Thickness-Dependent Hardness of SiO2 Thin Films Using Nanoindentation

Coatings ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 23
Author(s):  
Weiguang Zhang ◽  
Jijun Li ◽  
Yongming Xing ◽  
Xiaomeng Nie ◽  
Fengchao Lang ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Grain Size ◽  
Integrated Circuits ◽  
Film Thickness ◽  
Depth Range ◽  
Micro Electro Mechanical Systems ◽  
Si Substrates ◽  
Sio2 Thin Film ◽  
Average Grain Size

SiO2 thin films are widely used in micro-electro-mechanical systems, integrated circuits and optical thin film devices. Tremendous efforts have been devoted to studying the preparation technology and optical properties of SiO2 thin films, but little attention has been paid to their mechanical properties. Herein, the surface morphology of the 500-nm-thick, 1000-nm-thick and 2000-nm-thick SiO2 thin films on the Si substrates was observed by atomic force microscopy. The hardnesses of the three SiO2 thin films with different thicknesses were investigated by nanoindentation technique, and the dependence of the hardness of the SiO2 thin film with its thickness was analyzed. The results showed that the average grain size of SiO2 thin film increased with increasing film thickness. For the three SiO2 thin films with different thicknesses, the same relative penetration depth range of ~0.4–0.5 existed, above which the intrinsic hardness without substrate influence can be determined. The average intrinsic hardness of the SiO2 thin film decreased with the increasing film thickness and average grain size, which showed the similar trend with the Hall-Petch type relationship.

Effects of Solubility Limit and the Presence of Ultra-Fine Al6Fe on the Kinetics of Grain Growth in Dilute Al-Fe Alloys

2007 ◽  
Vol 550 ◽  
pp. 339-344 ◽  
Author(s):  
Shigeo Saimoto ◽  
Hai Ou Jin
Keyword(s):  
Grain Size ◽  
Cold Rolling ◽  
Grain Growth ◽  
Solubility Limit ◽  
Rolled Sheet ◽  
Migration Rates ◽  
Cold Rolled ◽  
Fe Alloys ◽  
Grain Growth Kinetics ◽  
Kinetics Of

A nominally pure Al slab was thermo-mechanically treated to result in a near random texture of 90 m grain size. Subsequent cold rolling with intermediate anneals at 230, 275, and 300°C reduced the Fe solute to near equilibrium compositions below 0.5 ppm atomic. The final cold rolled sheet continuously recrystallized; grain growth of this structure is reported. A grain-growth kinetics mapping was generated, correlating the parameters of Fe-in-Al solubility limit, Fe diffusivities in the grain boundaries and the Al lattice and the activation energies for migration rates.

Simulation of Ideal Grain Growth Using the Multi-Phase-Field Model

2007 ◽  
Vol 558-559 ◽  
pp. 1177-1181 ◽  
Author(s):  
Philippe Schaffnit ◽  
Markus Apel ◽  
Ingo Steinbach
Keyword(s):  
Grain Size ◽  
Grain Growth ◽  
Phase Field ◽  
Large Scale ◽  
Field Model ◽  
Three Dimensional ◽  
Phase Field Model ◽  
Two Dimensions ◽  
Von Neumann ◽  
Average Grain Size

The kinetics and topology of ideal grain growth were simulated using the phase-field model. Large scale phase-field simulations were carried out where ten thousands grains evolved into a few hundreds without allowing coalescence of grains. The implementation was first validated in two-dimensions by checking the conformance with square-root evolution of the average grain size and the von Neumann-Mullins law. Afterwards three-dimensional simulations were performed which also showed fair agreement with the law describing the evolution of the mean grain size against time and with the results of S. Hilgenfeld et al. in 'An Accurate von Neumann's Law for Three-Dimensional Foams', Phys. Rev. Letters, 86(12)/2685, March 2001. Finally the steady state grain size distribution was investigated and compared to the Hillert theory.

Electroplated Cu Recrystallization in Damascene Structures at Elevated Temperatures

1999 ◽  
Vol 564 ◽  
Author(s):  
Qing-Tang Jiang ◽  
Michael E. Thomas ◽  
Gennadi Bersuker ◽  
Brendan Foran ◽  
Robert Mikkola ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Grain Size ◽  
Film Thickness ◽  
Grain Growth ◽  
Elevated Temperatures ◽  
Retardation Effect ◽  
Cu Films ◽  
Grain Sizes ◽  
Geometrical Constraints ◽  
The Difference

AbstractTransformations in electroplated Cu films from a fine to course grain crystal structure (average grain sizes went from ∼0.1 µm to several microns) were observed to strongly depend on film thickness and geometry. Thinner films underwent much slower transformations than thicker ones. A model is proposed which explains the difference in transformation rates in terms of the physical constraint experienced by the film since grain growth in thinner films is limited by film thickness. Geometrical constraints imposed by trench and via structures appear to have an even greater retardation effect on the grain growth. Experimental observations indicate that it takes much longer for Cu in damascene structures to go through grain size transformations than blanket films.

The Correlation Theory of 2D Normal Grain Growth

2004 ◽  
Vol 467-470 ◽  
pp. 1081-1086 ◽  
Author(s):  
M.W. Nordbakke ◽  
N. Ryum ◽  
Ola Hunderi
Keyword(s):  
Grain Size ◽  
Size Distribution ◽  
Grain Growth ◽  
Grain Size Distribution ◽  
Computer Simulations ◽  
Mean Field Theory ◽  
Mean Field ◽  
Grain Structures ◽  
Spatial Grain ◽  
Kinetics Of

Computer simulations of 2D normal grain growth have shown that size correlations between adjacent grains exist in 2D grain structures. These correlations prevail during the coarsening process and influence on the kinetics of the process and on the grain size distribution. Hillert’s analysis starts with the assumption that all grains in the structure have the same environment. Since computer simulations contradict this assumption, the mean-field theory for normal grain growth needs to be modified. A first attempt was made by Hunderi and Ryum, who modified Hillert’s growth law to include the effect of spatial grain size correlations. In the 1D case the distributions derived by means of the modified growth law agreed well with simulation data. However, the distribution derived for 2D grain growth retained unwanted properties of the Hillert distribution. We review some recent progress in developing a mean-field statistical theory. A paradox related to curvilinear polygons is shown to support the expectation that the grain size distribution has a finite cutoff.

Secondary Grain Growth in Heavily Doped Polysilicon During Rapid Thermal Annealing

1991 ◽  
Vol 230 ◽  
Author(s):  
S. Batra ◽  
K. Park ◽  
M. Lobo ◽  
S. Banerjee
Keyword(s):  
Grain Size ◽  
Film Thickness ◽  
Grain Growth ◽  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Silicon On Insulator ◽  
Active Devices ◽  
Drastic Increase ◽  
Heavily Doped ◽  
Soi Technology

AbstractTo successfully implement Silicon-on-Insulator (SOI) technology using polysilicon-on-oxide, it is necessary to maximize the grain size such that the active devices are entirely within very large single crystal grains. A drastic increase in grain size in polysilicon has been reported due to secondary grain growth in ultra-thin, heavily n-type doped films upon regular furnace annealing. Very little work has been undertaken, however, to study secondary grain growth during Rapid Thermal Annealing (RTA).This paper is a study of the grain growth mechanism in heavily P-doped, amorphous silicon films during RTA. Secondary grains as large as 16 μm have been obtained in 160 nm thick films after a 180 s RTA at 1200 °C, representing a grainsize- to-film-thickness-ratio of 100:1. This is the largest secondary grain size and grain-size-to-film-thickness reported in the literature. A detailed analysis of negatively charged silicon vacancies has also been employed to explain the lower activation energy (1.55 eV) of secondary grain growth compared to that of normal grain growth (2.4 eV).

Topology Based Growth Law and New Analytical Grain Size Distribution Function of 3D Grain Growth

2007 ◽  
Vol 558-559 ◽  
pp. 1183-1188 ◽  
Author(s):  
Peter Streitenberger ◽  
Dana Zöllner
Keyword(s):  
Grain Size ◽  
Distribution Function ◽  
Size Distribution ◽  
Grain Growth ◽  
Grain Size Distribution ◽  
Three Dimensional ◽  
Size Distribution Function ◽  
Change Rate ◽  
Grain Sizes ◽  
Self Similar

Based on topological considerations and results of Monte Carlo Potts model simulations of three-dimensional normal grain growth it is shown that, contrary to Hillert’s assumption, the average self-similar volume change rate is a non-linear function of the relative grain size, which in the range of observed grain sizes can be approximated by a quadratic polynomial. In particular, based on an adequate modification of the effective growth law, a new analytical grain size distribution function is derived, which yields an excellent representation of the simulated grain size distribution.

Effect of the Intercalation of the Carbon Layer on the Kinetics of Grain Growth of FePt Magnetic Thin Film during Ordering Reaction - A Monte Carlo Simulation Study

2007 ◽  
Vol 558-559 ◽  
pp. 1237-1242
Author(s):  
M.C. Kim ◽  
D.A. Kim ◽  
Joong Kuen Park
Keyword(s):  
Thin Film ◽  
Monte Carlo Simulation ◽  
Grain Size ◽  
Monte Carlo ◽  
Grain Growth ◽  
Carbon Layer ◽  
Carbon Addition ◽  
Monte Carlo Simulation Study ◽  
Ordering Kinetics ◽  
Kinetics Of

The effect of carbon addition on the grain growth and ordering kinetics of FePt film has been experimentally studied by sputter-depositing a monolithic FePt-20at.%C film of 24 nm. Carbon addition of 20at.% to FePt thin film in a form of FePt (20 nm)/Cn (4 nm) (n = 1, 4) significantly reduced both the grain growth and ordering kinetics. Reducing the thickness of carbon layer, i.e. from n = 1 to n = 4, led to a much finer grain size distribution as well as to a finer grain size. The Monte Carlo simulation study indicated that the decrease of grain growth and ordering kinetics is primarily due to a continuous decrease of the mobility of order – disorder inter-phase with the progress of ordering reaction. This can eventually lead to a stable 2-phase grain structure inter-locked by low mobility inter-phases and is responsible for the formation of a fine grain size distribution in the FePt/Cn film with n = 4.

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