Printed assemblies of ultrathin, microscale inorganic light emitting diodes for deformable and semitransparent displays

A method for making an array of LEDs, said method comprising the steps of:

• providing a sapphire growth substrate having a receiving surface;
• forming a GaN epilayer on said receiving surface via epitaxial growth;
• wherein said GaN epilayer is a GaN multilayer comprising at least one p-doped GaN semiconductor layer in electrical contact with at least one n-doped GaN semiconductor layer, said GaN multilayer having a first contact surface;
• bonding said first contact surface of said GaN multilayer to a handle substrate;
• releasing said GaN multilayer from said growth substrate, wherein said GaN multilayer remains bonded to said handle substrate, thereby exposing a second contact surface of said GaN multilayer;
• patterning said second contact surface of said GaN multilayer with a mask, thereby generating exposed regions and one or more masked regions of said second contact surface;
• removing material from said exposed regions by etching said exposed regions, thereby generating one or more LED device structures supported by said handle substrate;
• at least partially releasing said one or more LED device structures from said handle substrate;
• and
• transferring at least a portion of said one or more LED device structures from said handle substrate to a device substrate via dry transfer contact printing, thereby making said array of LEDs.

A method for making an array of LEDs, said method comprising the steps of:

• providing a silicon growth substrate having a (111) orientation and having a receiving surface;
• generating a GaN multilayer on said receiving surface of said growth substrate via epitaxial growth, said GaN multilayer comprising at least one p-type GaN layer in electrical contact with at least one n-type GaN layer, said GaN multilayer having a contact surface;
• patterning said contact surface of said GaN multilayer with a mask, thereby generating exposed regions and one or more masked regions of said GaN multilayer;
• removing material from said exposed regions by etching said exposed regions and into said growth substrate, thereby exposing a portion of said growth substrate and generating one or more LED device structures;
• at least partially releasing said one or more LED device structures from said growth substrate by anisotropic etching said exposed portion of said growth substrate;
• and
• transferring at least a portion of said one or more LED device structures from said growth substrate to a device substrate via dry transfer contact printing, thereby making said array of LEDs.

A method for making an array of LEDs, said method comprising the steps of:

• providing a sapphire growth substrate having a receiving surface;
• providing a sacrificial layer on said receiving surface of said growth substrate;
• generating a GaN multilayer on said sacrificial layer via epitaxial growth, said GaN multilayer comprising at least one p-type GaN layer in electrical contact with at least one n-type GaN layer, said GaN multilayer having a contact surface;
• patterning said contact surface of said GaN multilayer with a mask, thereby generating exposed regions and one or more masked regions of said GaN multilayer;
• removing material from said exposed regions by etching said exposed regions, thereby exposing a portion of said sacrificial layer and generating one or more LED device structures;
• at least partially releasing said one or more LED device structures from said growth substrate by removing at least a portion of said sacrificial layer using directional etching, electrochemical etching or photoelectrochemical etching;
• and
• transferring at least a portion of said one or more LED device structures from said growth substrate to a device substrate via dry transfer contact printing, thereby making said array of LEDs.

A method for making an array of LEDs, said method comprising the steps of:

• providing a sapphire growth substrate having a receiving surface;
• generating a GaN multilayer on said sapphire growth substrate via epitaxial growth, said GaN multilayer comprising at least one p-type GaN layer in electrical contact with at least one n-type GaN layer, said GaN multilayer having a first contact surface, wherein said GaN multilayer and said sapphire growth substrate meet at an interface;
• bonding said first contact surface of said GaN multilayer to a handle substrate;
• exposing said interface between said GaN multilayer and said sapphire growth substrate to electromagnetic radiation;
• releasing said GaN multilayer from said growth substrate wherein said GaN multilayer remains bonded to said handle substrate, thereby exposing a second contact surface of said GaN multilayer;
• patterning said second contact surface of said GaN multilayer with a mask, thereby generating exposed regions and one or more masked regions of said GaN multilayer;
• removing material from said exposed regions by etching said exposed regions, thereby generating one or more LED device structures;
• at least partially releasing said one or more LED device structures from said handle substrate;
• and
• transferring at least a portion of said one or more LED device structures from said handle substrate to a device substrate via dry transfer contact printing, thereby making said array of LEDs.

A method for making an array of LEDs, said method comprising the steps of:

• providing a sapphire growth substrate having a receiving surface;
• providing a sacrificial layer on said receiving surface of said sapphire growth substrate;
• providing an etch block layer on said sacrificial layer;
• generating a GaN multilayer on said etch block layer via epitaxial growth, said GaN multilayer comprising at least one p-type GaN layer in electrical contact with at least one n-type GaN layer, said GaN multilayer having a contact surface;
• patterning said contact surface of said GaN multilayer with a mask, thereby generating exposed regions and one or more masked regions of said GaN multilayer;
• removing material from said exposed regions by etching said exposed regions, thereby exposing a portion of said sacrificial layer and generating one or more LED device structures;
• at least partially releasing said one or more LED device structures from said growth substrate by removing at least a portion of said sacrificial layer using directional etching, electrochemical etching or photoelectrochemical etching;
• and
• transferring at least a portion of said one or more LED device structures from said growth substrate to a device substrate via dry transfer contact printing, thereby making said array of LEDs.

A method for making an array of stacked LEDs, said method comprising the steps of:

• providing a sapphire growth substrate having a receiving surface;
• forming a GaN epilayer on said receiving surface via epitaxial growth, wherein said GaN epilayer is a GaN multilayer comprising at least one p-doped GaN semiconductor layer in electrical contact with at least one n-doped GaN semiconductor layer, said GaN multilayer having a first contact surface;
• bonding said first contact surface of said GaN multilayer to a handle substrate;
• releasing said GaN multilayer from said growth substrate, wherein said GaN multilayer remains bonded to said handle substrate, thereby exposing a second contact surface of said GaN multilayer;
• patterning said second contact surface of said GaN multilayer with a mask, thereby generating exposed regions and one or more masked regions of said second contact surface;
• removing material from said exposed regions by etching said exposed regions, thereby generating one or more LED device structures supported by said handle substrate;
• at least partially releasing said one or more LED device structures from said handle substrate;
• transferring at least a portion of said one or more LED device structures from said handle substrate to a device substrate via dry transfer contact printing, thereby making an array of LED device structures;
• and
• transferring one or more additional LED device structures on top of at least a portion of the array of LED device structures, thereby making said array of stacked LEDs.

A method for making an array of stacked LEDs, said method comprising the steps of:

• providing a sapphire growth substrate having a receiving surface;
• forming a GaN epilayer on said receiving surface via epitaxial growth;
• wherein said GaN epilayer is a GaN multilayer comprising at least one p-doped GaN semiconductor layer in electrical contact with at least one n-doped GaN semiconductor layer, said GaN multilayer having a first contact surface;
• bonding said first contact surface of said GaN multilayer to a handle substrate;
• releasing said GaN multilayer from said growth substrate wherein said GaN multilayer remains bonded to said handle substrate, thereby exposing a second contact surface of said GaN multilayer;
• patterning said second contact surface of said GaN multilayer with a mask, thereby generating exposed regions and one or more masked regions of said second contact surface;
• removing material from said exposed regions by etching said exposed regions, thereby generating one or more LED device structures supported by said handle substrate;
• at least partially releasing said one or more LED device structures from said handle substrate;
• transferring at least a portion of said one or more LED device structures from said handle substrate to a device substrate via dry transfer contact printing, wherein said device substrate comprises an array of LED device structures and said transferring step transfers said at least a portion of said one or more LED device structures on top of at least a portion of said array of LED device structures, thereby making said array of stacked LEDs.

A method of making an electronic device, the method comprising the steps of:

• providing a growth substrate having a receiving surface;
• forming a semiconductor epilayer on said receiving surface via epitaxial growth, said semiconductor epilayer having a first contact surface;
• bonding said first contact surface of said semiconductor epilayer to a handle substrate;
• releasing said semiconductor epilayer from said growth substrate, wherein at least a portion of said semiconductor epilayer remains bonded to said handle substrate, thereby exposing a second contact surface of said semiconductor epilayer;
• fabricating one or more semiconductor structures from at least a portion of said semiconductor epilayer, wherein said one or more semiconductor structures are supported by said handle substrate;
• transferring at least one of said one or more semiconductor structures from said handle substrate to a device substrate via dry transfer contact printing, thereby assembling said semiconductor structures on said device substrate to make said electronic device.

A method of making an electronic device, the method comprising the steps of:

• providing a first growth substrate having a first receiving surface;
• forming a first semiconductor epilayer on said first receiving surface via epitaxial growth, said first semiconductor epilayer having a first contact surface;
• bonding said first contact surface of said first semiconductor epilayer to a handle substrate;
• releasing said first semiconductor epilayer from said first growth substrate, wherein at least a portion of said first semiconductor epilayer remains bonded to said handle substrate, thereby exposing a second contact surface of said first semiconductor epilayer;
• providing a second growth substrate having a second receiving surface;
• forming a second semiconductor epilayer on said second receiving surface via epitaxial growth;
• said second semiconductor epilayer having a third contact surface;
• bonding said third contact surface of said second semiconductor epilayer to said handle substrate, said first semiconductor epilayer or both;
• releasing said second semiconductor epilayer from said second growth substrate, wherein at least a portion of said second semiconductor epilayer remains bonded to said handle substrate, said first semiconductor epilayer or both, thereby exposing a fourth contact surface of said second semiconductor epilayer;
• fabricating one or more semiconductor structures from at least a portion of said first semiconductor epilayer, or said second semiconductor epilayer or both said first semiconductor epilayer and said second semiconductor epilayer, wherein said one or more semiconductor structures are supported by said handle substrate;
• transferring at least one of said one or more semiconductor structures from said handle substrate to a device substrate via dry transfer contact printing, thereby assembling said semiconductor structures on said device substrate to make said electronic device.