Abstract: A microLED mass transfer stamping system includes a stamp substrate with an array of trap sites, each configured with a columnar-shaped recess to temporarily secure a keel extended from a bottom surface of a microLED. In the case of surface mount microLEDs, the keel is electrically nonconductive. In the case of vertical microLEDs, the keel is an electrically conductive second electrode. The stamping system also includes a fluidic assembly carrier substrate with an array of wells having a pitch separating adjacent wells that matches the pitch separating the stamp substrate trap sites. A display substrate includes an array of microLED pads with the same pitch as the trap sites. The stamp substrate top surface is pressed against the display substrate, with each trap site interfacing a corresponding microLED site, and the microLEDs are transferred. Fluidic assembly stamp substrates are also presented for use with microLEDs having keels or axial leads.

Abstract: A method is provided for the selective harvest of microLED devices from a carrier substrate. Defect regions are predetermined that include a plurality of adjacent defective microLED devices on a carrier substrate. A solvent-resistant binding material is formed overlying the predetermined defect regions and exposed adhesive is dissolved with an adhesive dissolving solvent. Non-defective microLED devices located outside the predetermined defect regions are separated from the carrier substrate while adhesive attachment is maintained between the microLED devices inside the predetermined defect regions and the carrier substrate. Methods are also provided for the dispersal of microLED devices on an emissive display panel by initially optically measuring a suspension of microLEDs to determine suspension homogeneity and calculate the number of microLEDs per unit volume.

Abstract: A system and method are provided for repairing an emissive element display. If a defective emissive element is detected in a subpixel, a subpixel repair interface isolates the defective emissive element. The repair interface may be a parallel repair interface with n number of selectively fusible electrically conductive repair nodes, connected in parallel to a control line of the matrix. Alternatively, the repair interface may be a series repair interface with m number of repair nodes, selectively connectable to bypass adjacent (defective) series-connected emissive elements. If the subpixel emissive elements are connected in parallel, and a defective low impedance emissive element is detected, a parallel repair interface fuses open a connection between the defective emissive element and a matrix control line. If the subpixels include series-connected emissive elements, and a high impedance emissive element is detected, a series repair interface forms a connection bypassing the defective emissive element.

Abstract: Disclosed herein is a micro light emitting diode (microLED) display structure with emission from the back side of a transparent substrate, which can be manufactured by fluidic assembly. The architecture allows microLED displays or display tiles to be fabricated simply, with processing and interconnection only on one side of the backplane. The structure may incorporate reflectors in the fluidic assembly structures to direct substantially all of the emitted light toward the viewer. Also disclosed are microLEDs and emission backplanes designed to support a back emission display.

Abstract: A microLED mass transfer stamping system includes a stamp substrate with an array of trap sites, each configured with a columnar-shaped recess to temporarily secure a keel extended from a bottom surface of a microLED. In the case of surface mount microLEDs, the keel is electrically nonconductive. In the case of vertical microLEDs, the keel is an electrically conductive second electrode. The stamping system also includes a fluidic assembly carrier substrate with an array of wells having a pitch separating adjacent wells that matches the pitch separating the stamp substrate trap sites. A display substrate includes an array of microLED pads with the same pitch as the trap sites. The stamp substrate top surface is pressed against the display substrate, with each trap site interfacing a corresponding microLED site, and the microLEDs are transferred. Fluidic assembly stamp substrates are also presented for use with microLEDs having keels or axial leads.

Abstract: A method is provided for the selective harvest of microLED devices from a carrier substrate. Defect regions are predetermined that include a plurality of adjacent defective microLED devices on a carrier substrate. A solvent-resistant binding material is formed overlying the predetermined defect regions and exposed adhesive is dissolved with an adhesive dissolving solvent. Non-defective microLED devices located outside the predetermined defect regions are separated from the carrier substrate while adhesive attachment is maintained between the microLED devices inside the predetermined defect regions and the carrier substrate. Methods are also provided for the dispersal of microLED devices on an emissive display panel by initially optically measuring a suspension of microLEDs to determine suspension homogeneity and calculate the number of microLEDs per unit volume.

Abstract: A microLED mass transfer stamping system includes a stamp substrate with an array of trap sites, each configured with a columnar-shaped recess to temporarily secure a keel extended from a bottom surface of a microLED. In the case of surface mount microLEDs, the keel is electrically nonconductive. In the case of vertical microLEDs, the keel is an electrically conductive second electrode. The stamping system also includes a fluidic assembly carrier substrate with an array of wells having a pitch separating adjacent wells that matches the pitch separating the stamp substrate trap sites. A display substrate includes an array of microLED pads with the same pitch as the trap sites. The stamp substrate top surface is pressed against the display substrate, with each trap site interfacing a corresponding microLED site, and the microLEDs are transferred. Fluidic assembly stamp substrates are also presented for use with microLEDs having keels or axial leads.

Abstract: A uniform pressure gang bonding device and fabrication method are presented using an expandable upper chamber with an elastic surface. Typically, the elastic surface is an elastomer material having a Young's modulus in a range of 40 to 1000 kilo-Pascal (kPA). After depositing a plurality of components overlying a substrate top surface, the substrate is positioned over the lower plate, with the top surface underlying and adjacent (in close proximity) to the elastic surface. The method creates a positive upper chamber medium pressure differential in the expandable upper chamber, causing the elastic surface to deform. For example, the positive upper chamber medium pressure differential may be in the range of 0.05 atmospheres (atm) and 10 atm. Typically, the elastic surface deforms between 0.5 millimeters (mm) and 20 mm, in response to the positive upper chamber medium pressure differential.

Abstract: A method is provided for the selective harvest of microLED devices from a carrier substrate. Defect regions are predetermined that include a plurality of adjacent defective microLED devices on a carrier substrate. A solvent-resistant binding material is formed overlying the predetermined defect regions and exposed adhesive is dissolved with an adhesive dissolving solvent. Non-defective microLED devices located outside the predetermined defect regions are separated from the carrier substrate while adhesive attachment is maintained between the microLED devices inside the predetermined defect regions and the carrier substrate. Methods are also provided for the dispersal of microLED devices on an emissive display panel by initially optically measuring a suspension of microLEDs to determine suspension homogeneity and calculate the number of microLEDs per unit volume.

Abstract: A method is provided for the selective harvest of microLED devices from a carrier substrate. Defect regions are predetermined that include a plurality of adjacent defective microLED devices on a carrier substrate. A solvent-resistant binding material is formed overlying the predetermined defect regions and exposed adhesive is dissolved with an adhesive dissolving solvent. Non-defective microLED devices located outside the predetermined defect regions are separated from the carrier substrate while adhesive attachment is maintained between the microLED devices inside the predetermined defect regions and the carrier substrate. Methods are also provided for the dispersal of microLED devices on an emissive display panel by initially optically measuring a suspension of microLEDs to determine suspension homogeneity and calculate the number of microLEDs per unit volume.

Abstract: Disclosed herein is a micro light emitting diode (microLED) display structure with emission from the back side of a transparent substrate, which can be manufactured by fluidic assembly. The architecture allows microLED displays or display tiles to be fabricated simply, with processing and interconnection only on one side of the backplane. The structure may incorporate reflectors in the fluidic assembly structures to direct substantially all of the emitted light toward the viewer. Also disclosed are microLEDs and emission backplanes designed to support a back emission display.

Abstract: A method is provided for the selective harvest of microLED devices from a carrier substrate. Defect regions are predetermined that include a plurality of adjacent defective microLED devices on a carrier substrate. A solvent-resistant binding material is formed overlying the predetermined defect regions and exposed adhesive is dissolved with an adhesive dissolving solvent. Non-defective microLED devices located outside the predetermined defect regions are separated from the carrier substrate while adhesive attachment is maintained between the microLED devices inside the predetermined defect regions and the carrier substrate. Methods are also provided for the dispersal of microLED devices on an emissive display panel by initially optically measuring a suspension of microLEDs to determine suspension homogeneity and calculate the number of microLEDs per unit volume.

Abstract: A method is provided for the selective harvest of microLED devices from a carrier substrate. Defect regions are predetermined that include a plurality of adjacent defective microLED devices on a carrier substrate. A solvent-resistant binding material is formed overlying the predetermined defect regions and exposed adhesive is dissolved with an adhesive dissolving solvent. Non-defective microLED devices located outside the predetermined defect regions are separated from the carrier substrate while adhesive attachment is maintained between the microLED devices inside the predetermined defect regions and the carrier substrate. Methods are also provided for the dispersal of microLED devices on an emissive display panel by initially optically measuring a suspension of microLEDs to determine suspension homogeneity and calculate the number of microLEDs per unit volume.

Abstract: A fluidic assembly emissive display panel is presented with a plurality of wells exposing LED interfaces. Each LED interface is made up of a planar first interconnect platform having an x-axis first depth and is configured to accept an axial LED first electrode mounting wing. A planar second interconnect platform has the first depth and is configured to accept an axial LED second electrode mounting wing. A groove is interposed between the first and second interconnect platforms and has an x-axis second depth, greater than the first depth, and is configured to accept an axial LED body locking tooth. The axial LEDs have an inorganic LED body with two symmetrical locking teeth. First and second electrode mounting wings are electrically connected to corresponding LED interface first and second interconnect platforms, and aligned in a plane orthogonal to stacked LED body semiconductor layers.

Abstract: A uniform pressure gang bonding device and fabrication method are presented using an expandable upper chamber with an elastic surface. Typically, the elastic surface is an elastomer material having a Young's modulus in a range of 40 to 1000 kilo-Pascal (kPA). After depositing a plurality of components overlying a substrate top surface, the substrate is positioned over the lower plate, with the top surface underlying and adjacent (in close proximity) to the elastic surface. The method creates a positive upper chamber medium pressure differential in the expandable upper chamber, causing the elastic surface to deform. For example, the positive upper chamber medium pressure differential may be in the range of 0.05 atmospheres (atm) and 10 atm. Typically, the elastic surface deforms between 0.5 millimeters (mm) and 20 mm, in response to the positive upper chamber medium pressure differential.

Abstract: A system and method are provided for repairing an emissive element display. If a defective emissive element is detected in a subpixel, a subpixel repair interface isolates the defective emissive element. The repair interface may be a parallel repair interface with n number of selectively fusible electrically conductive repair nodes, connected in parallel to a control line of the matrix. Alternatively, the repair interface may be a series repair interface with m number of repair nodes, selectively connectable to bypass adjacent (defective) series-connected emissive elements. If the subpixel emissive elements are connected in parallel, and a defective low impedance emissive element is detected, a parallel repair interface fuses open a connection between the defective emissive element and a matrix control line. If the subpixels include series-connected emissive elements, and a high impedance emissive element is detected, a series repair interface forms a connection bypassing the defective emissive element.

Abstract: A uniform pressure gang bonding device and fabrication method are presented using an expandable upper chamber with an elastic surface. Typically, the elastic surface is an elastomer material having a Young's modulus in a range of 40 to 1000 kilo-Pascal (kPA). After depositing a plurality of components overlying a substrate top surface, the substrate is positioned over the lower plate, with the top surface underlying and adjacent (in close proximity) to the elastic surface. The method creates a positive upper chamber medium pressure differential in the expandable upper chamber, causing the elastic surface to deform. For example, the positive upper chamber medium pressure differential may be in the range of 0.05 atmospheres (atm) and 10 atm. Typically, the elastic surface deforms between 0.5 millimeters (mm) and 20 mm, in response to the positive upper chamber medium pressure differential.

Abstract: A system and method are provided for repairing an emissive element display. If a defective emissive element is detected in a subpixel, a subpixel repair interface isolates the defective emissive element. The repair interface may be a parallel repair interface with n number of selectively fusible electrically conductive repair nodes, connected in parallel to a control line of the matrix. Alternatively, the repair interface may be a series repair interface with m number of repair nodes, selectively connectable to bypass adjacent (defective) series-connected emissive elements. If the subpixel emissive elements are connected in parallel, and a defective low impedance emissive element is detected, a parallel repair interface fuses open a connection between the defective emissive element and a matrix control line. If the subpixels include series-connected emissive elements, and a high impedance emissive element is detected, a series repair interface forms a connection bypassing the defective emissive element.

Abstract: A system and method are provided for repairing an emissive display. Following assembly, the emissive substrate is inspected to determine defective array sites, and defect items are removed using a pick-and-remove process. In one aspect, the emissive substrate includes an array of wells, with emissive elements located in the wells, but not electrically connected to the emissive substrate. If the emissive elements are light emitting diodes (LEDs), then the emissive substrate is exposed to ultraviolet illumination to photoexcite the array of LED, so that LED illumination can be measured to determine defective array sites. The defect items may be determined to be misaligned, mis-located, or non-functional emissive elements, or debris. Subsequent to determining these defect items, the robotic pick-and-remove process is used to remove them. The pick-and-remove process can also be repurposed to populate empty wells with replacement emissive elements.

Abstract: A microLED mass transfer stamping system includes a stamp substrate with an array of trap sites, each configured with a columnar-shaped recess to temporarily secure a keel extended from a bottom surface of a microLED. In the case of surface mount microLEDs, the keel is electrically nonconductive. In the case of vertical microLEDs, the keel is an electrically conductive second electrode. The stamping system also includes a fluidic assembly carrier substrate with an array of wells having a pitch separating adjacent wells that matches the pitch separating the stamp substrate trap sites. A display substrate includes an array of microLED pads with the same pitch as the trap sites. The stamp substrate top surface is pressed against the display substrate, with each trap site interfacing a corresponding microLED site, and the microLEDs are transferred. Fluidic assembly stamp substrates are also presented for use with microLEDs having keels or axial leads.