KR20130142165A - Method and apparatus for improved singulation of light emitting devices - Google Patents

Abstract

The present invention is a laser-assisted singulation system and method for a light emitting electronic device fabricated on a substrate having a treatment surface and a depth extending from the treatment surface. The method includes providing a laser processing system having a picosecond laser having controllable parameters, controlling the laser parameter to form a light pulse from the picosecond laser and substantially removing the processing surface of the substrate. Forming a strain region having a depth in the range of about 50% of the depth, the width being less than about 5% of the region depth, applying mechanical stress to the substrate, and at least partially in cooperation with the linear strain region. Singulating said substrate by cleaving said substrate into said light emitting electronic device having a sidewall formed therein.

Description

Improved singulation method and device of light emitting device TECHNICAL FIELD

The present invention relates to laser-assisted singulation of light emitting devices fabricated on a common substrate. In particular, the present invention relates to the singulation of a light emitting device using a picosecond laser that is directed to produce a quartz region, wherein the quartz region begins on the surface of the substrate aligned with the quartz region and extends into the interior. In particular, the present invention relates to singulation of a light emitting device having a textured surface to improve the light emitting properties of the device.

Electronic devices are typically fabricated by accumulating multiple copies of the device in parallel on a common substrate and then singulating the devices into individual units. The substrate comprises a wafer of silicon or sapphire combined with a layer of metal (conductive), dielectric (insulating), or semi-conductive material to form an electronic device. 1 shows a typical wafer 10 supporting elements 12 arranged in rows and columns. These rows and columns form a street 14, 16 or straight line between the elements 12. This arrangement of elements 12 and streets 14, 16 can separate the wafers along a straight line, allowing the use of rotary saws and mechanical cleaving. Desirable properties for singulation techniques include die, which is a measure of the ability of a singulated device to withstand breakage under mechanical stress and a small kerf size that reduces the street size to allow a larger area of active devices per substrate. Smooth intact edges that increase fracture strength, and system throughput, which is the number of wafers that can be processed at an acceptable quality per hour, typically related to cutting speed and number of passes per cut. The substrate may be singulated by dicing, which is a process of singulating the substrate into individual devices by cutting through the streets of the row and column arrays using cutting tools such as saw blades. The substrate may also be scribed, in which the cutting tool makes a scribe or shallow trench of the substrate surface, and then a force is applied, typically mechanically, to initiate the crack in the scribe. Forming or cleaving the substrate. The semiconductor wafer to be singulated is temporarily attached to a stretchable adhesive film, commonly referred to as a die attach film (DAF), held by a circular frame. These DAFs can singulate the wafer while still maintaining control of the individual devices.

An important factor in device singulation for light emitting devices such as light emitting diodes (LEDs) or laser diodes is the die breaking strength, which is the degree of warpage that the singulated device can withstand without damage, at least in part, as a function of the singulation process. It includes. A singulation process that can damage the singulated edges of the material as a result of a heat affected zone (HAZ) that can surround the laser pulse position can reduce the die breaking strength of the resulting singulated device. Finally, the light output of the device as a function of the applied electrical energy is an important factor in determining the quality of the singulated device. Since the edge quality determines how much light is reflected back into the device and how much light is usefully transmitted from the device, the light output from the light emitting device is because the optical properties of the resulting edge are the determining factor of the light output. Is at least partly a function of the singulation process. Factors that determine edge quality include the presence of thermal debris, random faceting of broken edges, and damage to edges caused by HAZ. Finally, system throughput, the number of devices that can be singulated per unit time on a given machine, is an important factor in determining the satisfaction of singulation technology. Techniques for increasing quality at the expense of reducing system throughput are undesirable compared to techniques that do not reduce system throughput.

Lasers are advantageously applied to the singulation of electronic devices. Lasers have the advantage of not consuming expensive diamond coated saw blades, cutting faster with smaller cuffs than saws, and cutting off patterns other than straight lines when required. Problems with lasers include contamination from debris and damage caused to the device by excessive heat. U.S. Patent No. 6,676,878 ("LASER SEGMENTED CUTTING", inventor James N. O'Brien, Lian-Cheng Zou, and Yunlong Sun), assigned to the assignee of the present application, controls the system's throughput while maintaining device quality by controlling heat accumulation. To improve, wafer singulation methods using multi-pass ultraviolet laser pulses are discussed. The singulation effect on the light output of the light emitting device is not discussed in this patent. U.S. Pat.No. 7,804,043 ("METHOD AND APPARATUS FOR DICING OF THIN AND ULTRA THIN SEMICONDUCTOR WAFER USING ULTRAFAST PULSE LASER", inventor Tan Deshi) uses an ultrafast (femtosecond or pico-gun) pulse duration to control fragment generation. Discuss. The '043 patent proposes a way to scribe or dice a wafer without generating ultra-fast pulses of large amounts of thermal debris. The effect that such fragments may have on the light output from the light emitting device is not discussed in the '043 patent. Apparently ultrafast pulses can use the energy of the pulses to connect energy to the material to be removed quickly enough to substantially ablate the material rather than thermally remove it. Ablation is the process by which material is removed from a substrate by connecting enough energy into the material fast enough that atoms of the material separate into the plasma clouds of charged molecules, nuclei, and electrons. It is melted into a liquid and vaporized into a gas or directly sublimed into a gas by laser energy. Additionally, the material can also be removed from the laser processing site by releasing a liquid or solid material from the expansion of the heated gas at the laser processing site. In practice, any laser material removal is generally a combination of an ablation process and a thermal process. Highly excited laser pulses with short pulse durations tend to induce material removal in an ablation fashion rather than thermally. The same pulse energy applied over longer pulse durations tends to make the material removal thermal rather than ablation.

Laser-assisted singulation of a light emitting device presents a problem because the quality of the edges remaining on the device by the singulation process can affect the light output, and therefore value, of the final device. US Patent No. 6,580,054 assigned to the assignee of this patent application ("SCRIBING SAPPHINRE SUBSTRATES WITH A SOLID STATE LASER", inventors Kuo-Ching Liu, Pei Hsien Fang, Dan Dere, Jenn Liu, Jih-Chuang Huang, Antonio Lucero, Scott Pinkham, Steven Oltrogge, and Duane Middlebusher discuss the use of ultraviolet laser pulses to scribe sapphire materials used to fabricate light emitting devices. U.S. Pat.No. 6,992,026 ("LASER PROCESSING METHOD AND LASER PROCESSING APPARATUS", inventors Fumitsugo Fukuyo, Kenshi Fukumitsu, Kaoki Uchiuyama, and Toahimitsu Wakuda), to guide mechanical cleaving while leaving the surface of an undamaged wafer after singulation. The formation of degraded regions in the wafer is discussed. None of the patents mentioned herein discuss the effect of laser-assisted singulation on device edge optical quality or its effect on light output.

Literature discussing edge quality and its optical properties is described in Hung-Wen Huang, C.F. Lai, W.C. Wang, T.C. Lu, H.C. Kuo, S.C. Wang, R. J. Tsai, and C. C. Yu, "Efficiency Enhancement of GaN-Based Power-Chip LEDs with Sidewall Roughness by Natural Lithography", Electrochemcal and Solid State Letters, Vol. 10 No. (2). This paper discusses the light output of light emitting diodes (LEDs) as a function of sidewall roughness. This paper discloses a method of controlling sidewall roughness by adding an additional step of etching with polystyrene beads. The etching step with polystyrene beads adds new equipment, adds a requirement not related to the basic operation of light emitting device singulation, and thus adds cost to the process and reduces the throughput of the overall process. The authors do not consider or understand that sidewall quality can be preferably affected or controlled using lasers during singulation.

Thus, a cost-competitive, reliable and repeatable method for laser-assisted singulation of light emitting devices from a substrate that controls sidewall quality to provide improved light output from the device while maintaining device quality and system throughput is ongoing. It is required.

The present invention is a laser-assisted singulation system and method for a light emitting electronic device fabricated on a substrate having a treatment surface and a depth extending from the treatment surface. The method includes providing a laser processing system having a picosecond laser having controllable parameters, controlling the laser parameter to form a light pulse from the picosecond laser and substantially removing the processing surface of the substrate. Forming a strain region having a depth within a range greater than about 50% of the depth, and having a width less than about 5% of the depth of the region, applying mechanical stress to the substrate, and cooperatively with the linear strain region. Singulating the substrate by cleaving the substrate into the light emitting electronic device having at least partially formed sidewalls. Aspects of the present invention perform laser-assisted singulation of light emitting electronic devices fabricated on a substrate using a laser processing system. The laser processing system uses a pulsed picosecond laser with controllable laser parameters to form a strained region extending on the surface of the substrate on the surface of the substrate, the laser parameter limiting the size of the strained region in the transverse direction. Controlled to. The substrate is then singulated by exerting a mechanical stress on the substrate adjacent the strain region, thereby splitting the substrate along the facets containing the strain region. These faces, including the strained regions, operate to transmit at least about 80% of the light impinging on the faces emitted by the light emitting element.

Aspects of the present invention improve the light output from singulated light emitting devices by using laser pulse parameters that reduce the amount of thermal debris and control thermal damage to the substrate. Laser pulses of 532 nm or shorter wavelength with pulse widths less than about 10 ps exported at pulse repetition rates ranging from 75 kHz to 800 kHz are advantageously used to scribe sapphire substrates. The laser pulses are delivered to the substrate using an adaptive laser scribing system. These pulses are focused at a focus from less than about 1 micrometer to about 5 micrometers positioned relative to the substrate by the cooperation between the beam positioning optics and the motion control stage of the adaptive laser scribing system. By adjusting the laser parameters, the desired change in the substrate material will appear within and near the focal point and the undesirable change in the material around the focal point will be minimal. Desired effects of laser pulses include modifying the molecular or crystalline structure of the material to improve crack initiation or propagation, and providing a predetermined amount of texture at the edges irradiated after cleaving. By appropriate selection of the laser pulse parameters, deformations made to the substrate material can improve crack initiation and propagation, so that reduced mechanical forces are required to break the material after laser scribing, thus, chipping opportunities and other undesirable effects. Can reduce the effect of cleaving. Additional undesirable effects include heat debris and damage caused by heat affected zones (HAZ) near the irradiated location. HAZ damage involves the creation of microcracks that reduce die breaking strength and the creation of edge regions (which thus reduce light output) that absorb light and reflect it back into the device. Thermal debris also absorbs light and reflects it back into the device, further reducing the light output. Embodiments of the present invention form the deformation region in the substrate with just enough decomposed or deformed material to form a textured surface that does not extend far enough in the transverse direction to facilitate light transmission through the sidewalls and inhibit light transmission. Use laser parameters to facilitate

This aspect of the invention allows pico so that repeated laser pulses directed to the same neighborhood on the substrate for scribing induce a desired change in the substrate but do not raise the temperature of the HAZ sufficiently to cause undesirable thermal damage. Ultra laser pulses are used to direct them to the substrate to create a scribe on the substrate with the desired properties. This is accomplished by selecting laser parameters in addition to the wavelengths, pulse durations, repetition rates, pulse energies, and focal magnitudes listed above. These laser parameters include the spacing and timing of adjacent laser pulses on the substrate as the laser pulses as the laser beam moves relative to the substrate, which depends on the laser repetition rate, pulse duration, and is typically expressed in mm / s. . Typical laser beam speeds for embodiments of the invention are 20 to 1000 mm / s, in particular 50 to 450 mm / s.

Aspects of the present invention break up a scribed substrate by applying mechanical stress to the substrate adjacent the linear strain region to initiate a crack separating the substrate along the strain region. Forming a scribe on the substrate surface to initiate and guide the mechanical cleaving process can provide a resulting sidewall surface with better optical properties as compared to the case where cracks start in areas of deformation that do not reach the surface. Opto-System Co., Kyoto, 610-0313, Japan Ltd. By using mechanical cleaving tools, such as the Opto-System Semi Auto Breaker WBM-1000, or by mechanically stretching the DAF, the stress normally applied to the substrate causes cracks to start in the scribe area and Allow cracks to propagate If cleaving is performed on a substrate having an inner scribe without a surface scribe, it will tend to propagate cracks in an arbitrary direction towards the surface, resulting in a plurality of faces defined by small regions of the edges having a common surface orientation. These plurality of arbitrary aspects tend to reflect more light back into the singulated device, thereby lowering the light output. Cleaving a substrate with a surface scribe tends to produce edges with faces that reflect less light into the device because the resulting faces are generally aligned parallel to the scribing direction, thereby increasing the light output. have. Embodiments of the present invention singulate a substrate by performing cleaving along a scribe that is made on the surface of the substrate and extends into the substrate.

Through the present invention, a cost competitive, reliable and repeatable for laser-assisted singulation of a light emitting device from a substrate that controls sidewall quality to provide improved light output from the device while maintaining device quality and system throughput A method is provided.

1 is a wafer drawing.
2 is a laser processing system diagram.
3 is a scribed substrate view.
4 is an SEM image of the scribed substrate.
5 is an SEM image of a scribed substrate.

Embodiments of the invention perform laser-assisted singulation of light emitting electronic devices fabricated on a substrate using a laser processing system. The laser processing system uses a pulsed picosecond laser with controllable laser parameters to form a strained region on the surface of the substrate, which extends into the inner surface of the substrate, the laser parameter translating the extent of the strained region in the transverse direction. Controlled to restrict. The substrate is then singulated by applying mechanical stress to the substrate adjacent the strain region and by cleaving the substrate along the facets containing the strain region. This side including the modifying material improves light output from the light emitting device by providing a highly transmissive, diffused, non-reflective sidewall surface that improves the transmission of light from the inside of the device to the outside. Light reflected back into the device is undesirable because, firstly, it does not contribute to the device's useful light output, and secondly, it is resorbable and contributes to unwanted heat-accumulation which further increases the device's efficiency. Because it can be reduced. An aspect of the invention achieves improved light output efficiency of a light emitting device by improving the light transmission capability of the device sidewall as a result of the particular manner in which the substrate supporting the device is laser scribed for preparation for cleaving. By scribing the substrate supporting the light emitting element using appropriately selected laser parameters, the desired light transmission properties on the sidewalls formed by the singulation process will be provided in the deformation region.

Aspects of the present invention improve light output from singulated light emitting devices by utilizing laser pulse parameters that reduce the amount of thermal damage and thermal debris on the substrate. Laser pulses having a wavelength in the range from 150 to 3000 nm, in particular in the range from 150 to 600 nm, having a pulse width of less than 10 ns, in particular less than 300 ps, which are emitted at a pulse repetition rate in the range of 3 to 1500 kHz, in particular in the range of 75 to 600 kHz It is advantageously used for scribing substrates. The pulses are focused in focus in the range from less than about 1 micrometer to about 25 micrometers, in particular in the range from less than 1 micrometer to about 2 micrometers. Laser is manufactured by Electro Scientific Industires, Inc. of 97239, Oregon, USA. It is delivered to the board using an adaptive AccuScribe 2600 LED Laser Scribing System manufactured by the company. One adaptation implemented fits the solid-state infrared laser model Duetto manufactured by Time-Bandwidth Products AG, Z-8, Zurich, Switzerland. This laser emits a 10ps pulse at a 1064 nm wavelength, which is frequency doubled to a 532 nm wavelength using a solid-state harmonic generator, and optionally frequency tripled to a 355 nm wavelength using a solid-state harmonic generator. Optionally, Germany, 67661 Kaiserslautern, Opelstr. The Lumeral Rapid Green laser model SHG-SS manufactured by Lumera Laser GmbH, 10, can be fitted to the AccuScribe 2600 LED Laser Scribing System instead of the Time-Bandwidth Duetto. Lumera lasers emit 10 ps pulses at 1064 nm and 532 nm wavelengths. Using the dual output of the Lumera laser, a solid-state harmonic generator can be used to generate 355 nm output. These lasers have an output power of 0.1 to 1.5 watts.

2 shows a diagram of a laser scribing system 18 configured to scribe a substrate 30 according to an embodiment of the invention. The adapted laser scribing system 18 has a laser 20 that operates to emit a laser pulse 22. These pulses are shaped and steered by the beam shaping and steering optics 24 and then directed by the field optics 26 to the substrate 30. The debris control nozzle 28 utilizes vacuum and compressed air to prevent debris produced by the scribing process from falling on the surface of the substrate. The substrate 30 is moved relative to the laser pulses by a motion control stage 32 operating in cooperation with the beam shaping and steering optics 24. Additionally, the substrate 30 is aligned with the laser pulses 22 using an imaging system 34 including objective optics. The laser 20, beam shaping and steering optics 24, the motion control stage 32 and the imaging system 34 all operate under the control of the system controller 36.

3 shows a section of the substrate 40 having an upper surface 42 and a lower surface 44. On the upper surface 42 of the substrate, about 1 positioned relative to the substrate 40 by cooperation between the beam shaping and steering optics 24 of the adaptive laser scribing system 18 and the motion control stage 32. A scribe 46 is formed by the laser pulses 22 that are focused at a focus from less than micrometers up to 5 micrometers. The pulses are focused at points on or near surface 42 to perform scribing. In order to form a volume of deformable material 48 extending into the substrate 40 at a distance 50 from the upper surface 42 so that unwanted changes in the material around the focus appear minimally, and within and near the focus The laser parameters are adjusted so that the desired change in substrate material is seen at. The deformation region 48 is visible at the sidewall 52 perpendicular to the linear direction of the scribe and accounts for the lateral limit of the material deformed by the laser. Desired effects of laser pulses include altering the molecular or crystalline structure of the material to improve crack initiation or propagation, and providing a texture to the irradiated edge after cleaving. Cleaving will appear vertically along the line AA and linearly along the scribe when mechanical stress is applied to the substrate in the vicinity of the scribe. Undesirable effects include heat debris and damage caused by heat affected zone HAZ near the irradiated location. HAZ damage also includes the creation of microcracks that reduce die breaking strength and the creation of edge regions that absorb light and reflect it back into the device and thus reduce light output. Thermal debris also absorbs light and reflects it back into the device, further reducing light output. By using preselected laser parameters, it is possible to minimize this negative effect of laser scribing while achieving the desired effect.

Embodiments of the present invention utilize picosecond laser pulses and utilize such picosecond laser pulses so that repeated laser pulses directed near the same on the substrate do not raise the temperature of the HAZ sufficient to cause the desired change of the substrate while causing undesirable thermal damage. Directing the substrate to a substrate creates a scribe on the substrate to have the desired properties. This is accomplished by selecting laser parameters in addition to the wavelengths, pulse durations, repetition rates, pulse energies, and focal magnitudes listed above. These laser parameters include the spacing and timing of adjacent laser pulses on the substrate as the laser pulses as the laser beam moves relative to the substrate, which depends on the laser repetition rate, pulse duration, and is typically expressed in mm / s. . Typical laser beam speeds for embodiments of the invention are 20 to 1000 mm / s, in particular 50 to 450 mm / s. 4 shows a scanning electron microscope image of a wafer scribed in accordance with one embodiment of the present invention. 4 shows the scribed substrate 60 when viewed perpendicular to the sidewall 52. This figure shows the top surface 62 and the bottom surface 64 of the substrate along the sidewall 66. Top surface 62 shows scribe 68 with modifying material 70 inside substrate 60 that is visible on sidewall 52. The deformation region extends a predetermined distance 72 into the substrate. The transverse limits of the modifying material appearing in this image show that the vertical limit of the deformation is greater than the transverse limit, which is perpendicular to the linear scribe.

Aspects of the present invention break up a scribed substrate by applying mechanical stress to the substrate adjacent the scribe on the surface of the substrate to initiate and guide the mechanical cleaving process. By using a mechanical cleaving tool or mechanically stretching the DAF, the stress normally applied to the substrate will cause cracks to begin in the strained scribe region and cause cracks to propagate through the substrate from the top surface to the bottom surface. . Cleaving performed on a substrate with an inner scribe without adjacent surface scribes tends to propagate cracks in arbitrary directions towards the surface, thus leading to a plurality of faces defined by small regions of the edges having a common surface orientation. These plurality of arbitrary planes tend to reflect light back into the singulated device to reduce light output. By cleaving the substrate using a surface scribe, cracks with a scribe on the surface create edges with less reflecting light into the device and thus increasing light output because the resulting faces are generally aligned parallel to the scribing direction. Propagates 5 shows a scanning electron microscope image of a substrate after scribing in accordance with one embodiment of the present invention. FIG. 5 shows a substrate having a sidewall 86 and an upper surface 82 and a lower surface 84 formed by cleaving the substrate along a line similar to the line AA of FIG. 3 parallel to the linear direction of the scribe. . This image shows the location of the scribe 88, along with the deformation region 90 exposed by the cleaving on the sidewall 86. The deformation region extends into the substrate by a distance 92. These strained regions forming at least a portion of the sidewalls operate to transmit light originating from the device with greater efficiency than sidewalls or sidewalls having such strained regions extending transversely into the substrate by more than a few micrometers. .

Embodiments of the present invention are used to scribe a substrate that may be substantially transparent to the laser wavelength used by the system. In particular, sapphire wafers used as substrates for manufacturing light emitting diodes are substantially transparent to the wavelength of laser light used by preferred embodiments of the present invention. The sapphire wafer transmits about 85% of the laser energy at wavelengths between 355 nm and 4000 nm and transmits at least 60% of the laser energy at wavelengths between 190 nm and 355 nm. It is also common for the substrate to have a DAF applied to the top surface of the substrate supporting the active circuit. It is also often desirable to scribe the substrate on the upper surface of the street between the active elements. In this case, the DAF is loaded into the system with the attached substrate such that a laser pulse impinges on the substrate on the surface opposite to the surface for which scribing is desired. Since the substrate is substantially transparent to the laser wavelength used, the laser pulses can be transmitted through the substrate and focused on opposite surfaces of the substrate. Since the laser pulse has only enough energy to cause material deformation where the focal point intersects the substrate, scribing or deformation will occur near the surface opposite to where the laser pulse impinges on the substrate.

It will be apparent to those skilled in the art that many changes can be made in the details of the above-described embodiments of the invention without departing from the principles underlying the invention. Accordingly, the scope of the invention should be determined only by the following claims.

10 wafer 12 element
14, 16: Street 18: Laser Scribing System
20: laser 22: laser pulse
24 Beam forming and steering optical system 28 Fragment control nozzle
30, 40: substrate 32: motion control stage
34 Imaging System 42 Upper Surface
44: lower surface 46: scribe
48: modified material

Claims (29)

A laser-assisted singulation method of a light emitting electronic device fabricated on a substrate having a treatment surface and a depth extending from the treatment surface, the method comprising:
Providing a laser processing system having a picosecond laser having a selectable parameter,
Selecting the laser parameter to form an optical pulse from the picosecond laser, the depth being in a range greater than about 50% of the depth and substantially including the processing surface of the substrate and greater than about 5% of the region depth Forming a deformation region having a small width,
Singulating the substrate by applying mechanical stress to the substrate and splitting the substrate into the light emitting electronic device having sidewalls formed at least partially in cooperation with the linear strain region.
Laser-assisted singulation method of light emitting electronic device. The method of claim 1,
The laser parameter includes at least one of wavelength, pulse duration, pulse energy, pulse repetition rate, focal size, focal offset, and focal velocity.
Laser-assisted singulation method of light emitting electronic device. 3. The method of claim 2,
The wavelength is shorter or equal to about 600 nm
Laser-assisted singulation method of light emitting electronic device. 3. The method of claim 2,
The pulse duration is less than or equal to about 100 ps
Laser-assisted singulation method of light emitting electronic device. 3. The method of claim 2,
The pulse energy is greater than or equal to about 1.0 micro Joules
Laser-assisted singulation method of light emitting electronic device. 3. The method of claim 2,
The pulse repetition rate is between about 75 Hz and about 600 kHz
Laser-assisted singulation method of light emitting electronic device. 3. The method of claim 2,
The focal size ranges from less than about 1 micrometer to about 5 micrometers.
Laser-assisted singulation method of light emitting electronic device. 3. The method of claim 2,
The focal offset is between -50 micrometers and +50 micrometers relative to the substrate surface.
Laser-assisted singulation method of light emitting electronic device. 3. The method of claim 2,
The focal velocity is between about 25 and about 450 mm / s relative to the substrate surface
Laser-assisted singulation method of light emitting electronic device. A laser scribing system for laser-assisted singulation of a light emitting electronic device fabricated on a substrate having a treatment surface and a depth extending from the treatment surface, the system comprising:
A picosecond laser configured to generate a light pulse having at least one selectable parameter,
A laser optical system for controllably transporting the optical pulse to the substrate;
A motion control stage for controllably moving the substrate in association with the pulse;
Instructing the picosecond laser to emit the pulse, instructing the laser optics to deliver the pulse to the substrate, and having a depth in the range of 50% of the depth, substantially including the processing surface of the substrate, A controller, instructing the motion stage to move the substrate in relation to the pulse with the parameter operative to form a strain region having a width less than about 5% of the region depth.
Laser scribing system. 11. The method of claim 10,
The laser parameter includes at least one of wavelength, pulse duration, pulse energy, pulse repetition rate, focal size, focal offset, and focal velocity.
Laser scribing system. 12. The method of claim 11,
The wavelength is shorter or equal to about 600 nm
Laser scribing system. 12. The method of claim 11,
The pulse duration is less than or equal to about 100 ps
Laser scribing system. 12. The method of claim 11,
The pulse energy is greater than or equal to about 1.0 micro Joules
Laser scribing system. 12. The method of claim 11,
The pulse repetition rate is between about 75 Hz and about 600 kHz
Laser scribing system. 12. The method of claim 11,
The focal size ranges from less than about 1 micrometer to about 5 micrometers.
Laser scribing system. 12. The method of claim 11,
The focal offset is between -50 micrometers and +50 micrometers relative to the substrate surface.
Laser scribing system. 12. The method of claim 11,
The focal velocity is between about 25 and about 450 mm / s relative to the substrate surface
Laser scribing system. An improved light emitting electronic device having a treatment surface and sidewalls singulated from a substrate having a depth extending from the treatment surface using a laser scribing system having a substrate having a selectable parameter,
Textures are formed on the sidewalls to create a strained region with the laser that extends from the surface of the substrate into the substrate, enabling greater light output, thus improving the light emitting electronic device.
Improved light emitting electronic device. The method of claim 1,
The strain region substantially includes the treatment surface of the substrate and has a depth in the range of 50% of the depth and a width less than about 5% of the region depth
Laser-assisted singulation method of light emitting electronic device. A method of texturing a surface of a light emitting device to be singulated,
Applying a laser pulse having a selectable parameter,
The parameter is selected to create a deformation area on the surface that provides a desired texture.
A method of texturing a surface of a light emitting device to be singulated. 22. The method of claim 21,
The laser parameter includes at least one of wavelength, pulse duration, pulse energy, pulse repetition rate, focal size, focal offset, and focal velocity.
A method of texturing a surface of a light emitting device to be singulated. 23. The method of claim 22,
The wavelength is shorter or equal to about 600 nm
A method of texturing a surface of a light emitting device to be singulated. 23. The method of claim 22,
The pulse duration is less than or equal to about 100 ps
A method of texturing a surface of a light emitting device to be singulated. 23. The method of claim 22,
The pulse energy is greater than or equal to about 1.0 micro Joules
A method of texturing a surface of a light emitting device to be singulated. 23. The method of claim 22,
The pulse repetition rate is between about 75 kHz and about 600 kHz
A method of texturing a surface of a light emitting device to be singulated. 23. The method of claim 22,
The focal size ranges from less than about 1 micrometer to about 5 micrometers.
A method of texturing a surface of a light emitting device to be singulated. 23. The method of claim 22,
The focal offset is between -50 micrometers and +50 micrometers relative to the substrate surface.
A method of texturing a surface of a light emitting device to be singulated. 23. The method of claim 22,
The focal velocity is between about 25 and about 450 mm / s relative to the substrate surface
A method of texturing a surface of a light emitting device to be singulated.

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