Abstract:
Light emitting diode (LED) dies are fabricated by forming LED layers including a first conductivity type layer, a light-emitting layer, and a second conductivity type layer. Trenches are formed in the LED layers that reach at least partially into the first conductivity type layer. Electrically insulation regions are formed in or next to at least portions of the first conductivity type layer along the die edges. A first conductivity bond pad layer is formed to electrically contact the first conductivity type layer and extend over the singulation streets between the LED dies. A second conductivity bond pad layer is formed to electrically contact the second conductivity type layer, and extend over the singulation streets between the LED dies and the electrically insulated portions of the first conductivity type layer. The LED dies are mounted to submounts and the LED dies are singulated along the singulation streets between the LED dies.
Abstract:
A compliant bonding structure is disposed between a semiconductor device and a mount (40). In some embodiments, the device is a light emitting device. When the semiconductor light emitting device is attached to the mount, for example by providing ultrasonic energy to the semiconductor light emitting device, the compliant bonding structure collapses to partially fill a space between the semiconductor light emitting device and the mount. In some embodiments, the compliant bonding structure is plurality of metal bumps (32) that undergo plastic deformation during bonding. In some embodiments, the compliant bonding structure is a porous metal layer (46).
Abstract:
A process for forming electrical contacts for a semiconductor light emitting apparatus is disclosed. The light emitting apparatus has a first layer of first conductivity type, an active layer for generating light overlying the first layer, and a second layer of second conductivity type overlying the active layer. The process involves forming at least a first and a second elongate electrical contact through the second layer and the active layer to provide electrical connection to the first layer, the first and second contacts oriented at an angle to each other, the first contact having a first end in proximity with the second contact, the first end being sufficiently spaced apart from the second contact such that when current is supplied to the first layer through the contacts, current contributions from the first end of the first contact and the second contact in an area generally between the first end and the second contact cause a current density in the area that is approximately equal to a current density elsewhere along the first and second contacts.
Abstract:
Microfluidic system, including methods and apparatus, for processing fluid, such as by droplet generation. In some embodiments, the system may include a well and a channel component attached to the well. The channel component may include (a) a body, (b) an input tube (a "fluid pickup") projecting from a bottom surface of the body and having an open bottom end disposed in the input well, (c) a microchannel, and (d) a passage extending through the input tube and the body and connecting the well to the microchannel. The system may be configured to receive a sample- containing fluid in the well and retain the sample-containing fluid below a top end of the passage, until a pressure differential is created that drives at least a portion of the sample-containing fluid from the well via the passage and through the microchannel.
Abstract:
A process for forming electrical contacts for a semiconductor light emitting apparatus is disclosed. The light emitting apparatus has a first layer of first conductivity type, an active layer for generating light overlying the first layer, and a second layer of second conductivity type overlying the active layer. The process involves forming at least a first and a second elongate electrical contact through the second layer and the active layer to provide electrical connection to the first layer, the first and second contacts oriented at an angle to each other, the first contact having a first end in proximity with the second contact, the first end being sufficiently spaced apart from the second contact such that when current is supplied to the first layer through the contacts, current contributions from the first end of the first contact and the second contact in an area generally between the first end and the second contact cause a current density in the area that is approximately equal to a current density elsewhere along the first and second contacts.
Abstract:
Elements are added to a light emitting device to reduce the stress within the light emitting device caused by thermal cycling. Alternatively, or additionally, materials are selected for forming contacts within a light emitting device based on their coefficient of thermal expansion and their relative cost, copper alloys being less expensive than gold, and providing a lower coefficient of thermal expansion than copper. Elements of the light emitting device may also be structured to distribute the stress during thermal cycling.
Abstract:
A compliant bonding structure is disposed between a semiconductor device and a mount (40). In some embodiments, the device is a light emitting device. When the semiconductor light emitting device is attached to the mount, for example by providing ultrasonic energy to the semiconductor light emitting device, the compliant bonding structure collapses to partially fill a space between the semiconductor light emitting device and the mount. In some embodiments, the compliant bonding structure is plurality of metal bumps (32) that undergo plastic deformation during bonding. In some embodiments, the compliant bonding structure is a porous metal layer (46).
Abstract:
Described is a process for forming an LED structure using a laser lift-off process (72) to remove the growth substrate (e.g., sapphire) (28) after the LED die is bonded to a submount (56). The underside of the LED die has formed on it anode (36, 40) and cathode (34, 38) electrodes that are substantially in the same plane, where the electrodes cover at least 85% of the back surface of the LED structure. The submount has a corresponding layout of anode (60) and cathode (58) electrodes substantially in the same plane. The LED die electrodes and submount electrodes are ultrasonically welded together such that virtually the entire surface of the LED die is supported by the electrodes and submount. Other bonding techniques may also be used. No underfill is used. The growth substrate, forming the top of the LED structure, is then removed from the LED layers using a laser lift-off process. The extremely high pressures created during the laser lift-off process do not damage the LED layers due to the large area support of the LED layers by the electrodes and submount.
Abstract:
Systems, methods, and devices for forming an array of emulsions. An exemplary device comprises a frame and at least one or a plurality of separate microfluidic modules mounted to the frame and each configured to form an array of emulsions. In some embodiments, each module may be mounted by snap-fit attachment. The device also may include the same sealing member bonded to a top side of each module and hermetically sealing each of the modules. Another exemplary microfluidic device for forming an array of emulsions comprises a stack of layers bonded together. The stack may comprise a port layer forming a plurality of ports. Each port may have a top rim formed by a protrusion that encircles the central axis of the port. The rims may be coplanar with one another to facilitate bonding of a sealing member to each rim.
Abstract:
An assay performance system may include modules configured to store aqueous sample plates, conduct droplet generation or emulsification of aqueous samples, and to perform thermocycling and droplet reading functions. One or more samples may be emulsified and stored in an emulsified state for extended times prior to thermocycling. Accordingly, the assay performance system may include material handling systems and methods to accommodate the storage function.