Columbia University

Other

Samsung Electronics Co., Ltd.

James S Im

Robert S Sposili

Mark Albert Crowder

Paul C Van Der Wilt

Ui-Jin Chung

Alexander B Limanov

Wenkai Pan

Hyun-Jae Kim

Myung-Koo Kang

Sook-Young Kang

Su-Gyeong Lee

Insung Choi

Ruobing Song

Miao Yu

Qiongying Hu

Vernon Wong

Jae Beom Choi

Paul Christiaan Van Der Wilt

Yikang Deng

Paul Christian Van Der Wilt

Methods and systems for crystallizing a thin film provide an optics system configured to produce a laser spot beam directed towards the thin film and truncate the laser spot beam before the laser spot beam comes into contact with the thin film. The truncated laser spot beam is continually translated in a first direction while irradiating an amorphous silicon area of the thin film to generate a molten zone in the irradiated amorphous silicon area, where the thin film cools and solidifies to form crystal grains.

Systems and methods for spot beam and line beam crystallization

Methods and systems for crystallizing a thin film provide a laser beam spot that is continually advanced across tire thin film to create a sustained complete or partial molten zone that is translated across the thin film, and crystallizes to form uniform, small-grained crystalline structures or grains.

Methods and systems for spot beam crystallization

Methods and systems for crystallizing a thin film provide a laser beam spot that is continually advanced across the thin film to create a sustained complete or partial molten zone that is translated across the thin film, and crystallizes to form uniform, small-grained crystalline structures or grains.

A method for planarizing excimer laser annealed (ELA) polycrystalline thin films via irradiation. The method includes providing an ELA thin film having an oxide and a top surface with a first surface roughness defined at least by a first plurality of protrusions. The ELA thin film is etched to substantially remove the oxide. At least a portion of the etched ELA thin film is then irradiated using a short-pulse duration excimer laser beam, to form an irradiated thin film with a second surface roughness defined at least by a second plurality of protrusions. The second surface roughness is lower than the first surface roughness.

Laser irradiation induced surface planarization of polycrystalline silicon films

The present disclosure relates to a new generation of laser-crystallization approaches that can crystallize Si films for large displays at drastically increased effective crystallization rates. The particular scheme presented in this aspect of the disclosure is referred to as the advanced excimer-laser annealing (AELA) method, and it can be readily configured for manufacturing large OLED TVs using various available and proven technical components. As in ELA, it is mostly a partial-/near-complete-melting-regime-based crystallization approach that can, however, eventually achieve greater than one order of magnitude increase in the effective rate of crystallization than that of the conventional ELA technique utilizing the same laser source.

Advanced excimer laser annealing for thin films

Process and system for processing a thin film sample, as well as at least one portion of the thin film structure are provided. Irradiation beam pulses can be shaped to define at least one line-type beam pulse, which includes a leading portion, a top portion and a trailing portion, in which at least one part has an intensity sufficient to at least partially melt a film sample. Irradiating a first portion of the film sample to at least partially melt the first portion, and allowing the first portion to resolidify and crystallize to form an approximately uniform area therein. After the irradiation of the first portion of the film sample, irradiating a second portion using a second one of the line-type beam pulses to at least partially melt the second portion, and allowing the second portion to resolidify and crystallize to form an approximately uniform area therein. A section of the first portion impacted by the top portion of the first one of the line-type beam pulses is prevented from being irradiated by trailing portion of the second one of the line-type beam pulses.

Processes and systems for laser crystallization processing of film regions on a substrate utilizing a line-type beam, and structures of such film regions

In one aspect, the present disclosure relates to a method of processing a thin film including, while advancing a thin film in a first selected direction, irradiating a first region of the thin film with a first laser pulse and a second laser pulse, each laser pulse providing a shaped beam and having a fluence that is sufficient to partially melt the thin film and the first region re-solidifying and crystallizing to form a first crystallized region, and irradiating a second region of the thin film with a third laser pulse and a fourth laser pulse, each pulse providing a shaped beam and having a fluence that is sufficient to partially melt the thin film and the second region re-solidifying and crystallizing to form a second crystallized region, wherein the time interval between the first laser pulse and the second laser pulse is less than half the time interval between the first laser pulse and the third laser pulse.

Systems and methods for non-periodic pulse partial melt film processing

Collections of laterally crystallized semiconductor islands for use in thin film transistors and systems and methods for making same are described. A display device includes a plurality of thin film transistors (TFTs) on a substrate, such that the TFTs are spaced apart from each other and each include a channel region that has a crystalline microstructure and a direction along which a channel current flows. The channel region of each of the TFTs contains a crystallographic grain that spans the length of that channel region along its channel direction. Each crystallographic grain in the channel region of each of the TFTs is physically disconnected from and crystallographically uncorrelated with each crystallographic grain in the channel region of each adjacent TFT.

Collections of laterally crystallized semiconductor islands for use in thin film transistors

The disclosed systems and method for non-periodic pulse sequential lateral solidification relate to processing a thin film. The method for processing a thin film, while advancing a thin film in a selected direction, includes irradiating a first region of the thin film with a first laser pulse and a second laser pulse and irradiating a second region of the thin film with a third laser pulse and a fourth laser pulse, wherein the time interval between the first laser pulse and the second laser pulse is less than half the time interval between the first laser pulse and the third laser pulse. In some embodiments, each pulse provides a shaped beam and has a fluence that is sufficient to melt the thin film throughout its thickness to form molten zones that laterally crystallize upon cooling. In some embodiments, the first and second regions are adjacent to each other. In some embodiments, the first and second regions are spaced a distance apart.

Systems and methods for non-periodic pulse sequential lateral soldification

High throughput systems and processes for recrystallizing thin film semiconductors that have been deposited at low temperatures on a substrate are provided. A thin film semiconductor workpiece is irradiated with a laser beam to melt and recrystallize target areas of the surface exposed to the laser beam. The laser beam is shaped into one or more beamlets using patterning masks. The mask patterns have suitable dimensions and orientations to pattern the laser beam radiation so that the areas targeted by the beamlets have dimensions and orientations that are conducive to semiconductor recrystallization. The workpiece is mechanically translated along linear paths relative to the laser beam to process the entire surface of the work piece at high speeds. Position sensitive triggering of a laser can be used to generate laser beam pulses to melt and recrystallize semiconductor material at precise locations on the surface of the workpiece while it is translated on a motorized stage.

Single-shot semiconductor processing system and method having various irradiation patterns

The disclosed subject matter relates to the use of laser crystallization of thin films to create epitaxially textured crystalline thick films. In one or more embodiments, a method for preparing a thick crystalline film includes providing a film for crystallization on a substrate, wherein at least a portion of the substrate is substantially transparent to laser irradiation, said film including a seed layer having a predominant surface crystallographic orientation; and a top layer disposed above the seed layer; irradiating the film from the back side of the substrate using a pulsed laser to melt a first portion of the top layer at an interface with the seed layer while a second portion of the top layer remains solid; and re-solidifying the first portion of the top layer to form a crystalline laser epitaxial with the seed layer thereby releasing heat to melt an adjacent portion of the top layer.

Systems and methods for preparation of epitaxially textured thick films

Methods for processing an amorphous silicon thin film sample into a polycrystalline silicon thin film are disclosed. In one preferred arrangement, a method includes the steps of generating a sequence of excimer laser pulses, controllably modulating each excimer laser pulse in the sequence to a predetermined fluence, masking portions of each fluence controlled laser pulse in the sequence with a two dimensional pattern of slits to generate a sequence of fluence controlled pulses of line patterned beamlets, irradiating an amorphous silicon thin film sample with the sequence of fluence controlled slit patterned beamlets to effect melting of portions thereof, and controllably sequentially translating a relative position of the sample with respect to each of the fluence controlled pulse of slit patterned beamlets to thereby process the amorphous silicon thin film sample into a single or polycrystalline silicon thin film.

Uniform large-grained and grain boundary location manipulated polycrystalline thin film semiconductors formed using sequential lateral solidification and devices formed thereon

Crystallization of thin films using pulsed irradiation The method includes continuously irradiating a film having an x-axis and a y-axis, in a first scan in the x-direction of the film with a plurality of line beam laser pulses to form a first set of irradiated regions, translating the film a distance in the y-direction of the film, wherein the distance is less than the length of the line beam, and continuously irradiating the film in a second scan in the negative x-direction of the film with a sequence of line beam laser pulses to form a second set of irradiated regions, wherein each of the second set of irradiated regions overlaps with a portion of the first set of irradiated regions, and wherein each of the first and the second set of irradiated regions upon cooling forms one or more crystallized regions.

Systems and methods for the crystallization of thin films

In accordance with one aspect, the present invention provides a method for providing polycrystalline films having a controlled microstructure as well as a crystallographic texture. The methods provide elongated grains or single-crystal islands of a specified crystallographic orientation. In particular, a method of processing a film on a substrate includes generating a textured film having crystal grains oriented predominantly in one preferred crystallographic orientation; and then generating a microstructure using sequential lateral solidification crystallization that provides a location-controlled growth of the grains orientated in the preferred crystallographic orientation.

Growing community of inventors

New York, NY, United States of America

James S Im