Polycrystalline Si films with unique microstructures formed from amorphous Si films by non‐thermal equilibrium flash lamp annealing

Ohdaira, Keisuke; Nishikawa, Takuya; Shiba, Kazuhiro; Takemoto, Hiroyuki; Matsumura, Hideki

doi:10.1002/pssc.200982820

Cited by 9 publications

(5 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…One such morphology demonstrates large individual grains of silicon in an edge-directed layout, with ridges at the intersection of grain fronts, while another is a randomized morphology with significant planar void fraction. These morphologies are referred to by various names in literature (11), (12), but will be referenced as "ridge-associated" (RA) and "void-associated" (VA) in this paper. The comparative analysis of these two structures provides fundamental understanding of the FLA response for TFT applications.…”

Section: Previous Workmentioning

confidence: 99%

Flash Lamp Annealed Polycrystalline Silicon TFT Dependence on Surface Morphology and the Back-Channel Material Interface

2019

View full text Add to dashboard Cite

This work studies the operation of polycrystalline silicon p-channel TFTs prepared via Flash Lamp Annealing (FLA). Silicon nitride was investigated as a back-channel interface layer to suppress void formation via dewetting of molten silicon. Predefined polygons of amorphous silicon were crystallized on display glass using single-pulse FLA exposure. Two distinct surface morphologies were realized within the same exposed region as a result of the underlying silicon nitride film and localized variation in the substrate thermal contact during PECVD deposition of amorphous silicon. While both resulting morphologies have polysilicon grains on micron scale, differences in TFT electrical behavior appear to coincide with differences in grain structure and boundary regions. The electrical results also indicate inferior electrical performance in response to the back-channel silicon nitride in comparison to results demonstrated on SiO2. Extracted parameters provide a quantitative assessment of the device operation as related to surface morphology and the back-channel material interface.

show abstract

Section: Previous Workmentioning

confidence: 99%

Flash Lamp Annealed Polycrystalline Silicon TFT Dependence on Surface Morphology and the Back-Channel Material Interface

2019

View full text Add to dashboard Cite

show abstract

“…When EC acts as a crystallization-initiating effect, it typically starts by locally heating the material and then sustains itself by releasing the latent heat of fusion during the transition from the amorphous phase to the crystalline phase, resulting in a crystallization front propagating in a direction parallel to the film surface through the material. EC occurs in a wide variety of materials, such as in (In, Ga) Sb, Bi, Ge, Si, Se 80 Te 20 , and others . A thorough comprehension of the processes underlying this EC procedure may allow for effective improvements and control over the properties of crystalline thin films.…”

Section: Introductionmentioning

confidence: 99%

Explosive Crystallization Characteristic of Ge–Cu–Te Thin Films for Phase-Change Memory

Wang

Chen

2023

Crystal Growth & Design

View full text Add to dashboard Cite

Ge–Cu–Te thin films were investigated experimentally for their initial crystallization characteristics and their correlation with electrical behaviors as phase-change materials for application in phase-change random access memory (PCRAM). Explosive crystallization (EC) with random orientation was observed as an initiating effect on crystallization during the early stage of crystallization for Ge–Cu–Te thin films. Both the tetrahedral coordination environment and triangular Cu atoms clusters consisting of threefold rings for Ge–Cu–Te thin films contribute to the initiation of EC. Crystallization progresses from the surface toward the bulk of the thin films, resulting in grain growth through the thickness of the thin films. Thicker films can encourage EC by reducing heat loss and producing a thicker liquid layer as a result of more significant temperature gradients near the phase-change front. Moreover, providing additional external heat by extending the annealing time also pushes EC. Finally, electrical transport measurements using the Hall system demonstrated that conductivity is increased by a more continuous EC network that concentrates more carriers. The authors consider that the above results are beneficial for understanding the phase-change mechanism of Ge–Cu–Te phase-change materials.

show abstract

“…Short-time annealing methods have been widely used for the crystallization of a-Si films because of high productivity. [10][11][12][13][14][15][16][17][18][19][20][21][22][23] In the short-time annealing methods, heating duration is one of the most important factors for the crystallization of thick a-Si films and the suppression of thermal damage to substrates. Rapid thermal annealing (RTA) has an annealing duration of >1 s, leading to the heating of entire substrates along the depth.…”

Section: Introductionmentioning

confidence: 99%

Crystallization of electron beam evaporated a-Si films on textured glass substrates by flash lamp annealing

Kurata¹,

Ohdaira²

2019

Jpn. J. Appl. Phys.

Self Cite

View full text Add to dashboard Cite

We investigate the crystallization of amorphous silicon (a-Si) films, by flash lamp annealing (FLA), formed by electron beam (EB) evaporation on textured glass substrates. We confirmed that EB-evaporated a-Si films formed on textured glass can be crystallized by FLA. Optical reflectance on EB-evaporated a-Si can be reduced by using the textured glass, leading to a reduction in the fluence of a FL pulse required for the crystallization. The fluence of a FL pulse for the crystallization of EB-evaporated a-Si films tends to increase with temperature during EB evaporation of a-Si films. The pre-existing crystal grains in precursor Si films may affect the mechanism of their crystallization. The usage of textured glass substrates leads the formation of polycrystalline Si (poly-Si) films with fine grains. This may result from the prevention of lateral thermal growth and the suppression of explosive crystallization (EC). Unlike in the case of the crystallization of EB-evaporated a-Si films on flat glass substrates, poly-Si films formed on textured glass substrates are not cracked. This may be due to the suppression of the emergence of EC.

show abstract

Polycrystalline Si films with unique microstructures formed from amorphous Si films by non‐thermal equilibrium flash lamp annealing

Cited by 9 publications

References 15 publications

Flash Lamp Annealed Polycrystalline Silicon TFT Dependence on Surface Morphology and the Back-Channel Material Interface

Flash Lamp Annealed Polycrystalline Silicon TFT Dependence on Surface Morphology and the Back-Channel Material Interface

Explosive Crystallization Characteristic of Ge–Cu–Te Thin Films for Phase-Change Memory

Crystallization of electron beam evaporated a-Si films on textured glass substrates by flash lamp annealing

Contact Info

Product

Resources

About