An apparatus for bonding semiconductor chips may comprise transfer rails configured to transfer substrates, loading members configured to load the substrates onto the transfer rails, unloading members configured to unload the substrates from the transfer rails, a first wafer supply unit configured to supply a first wafer including semiconductor chips, and/or a bonding unit configured to bond the semiconductor chips to the substrates. An apparatus for bonding semiconductor chips may comprise a transfer rail configured to transfer substrates, loading members configured to load the substrates onto the transfer rail, unloading members configured to unload the substrates from the transfer rail, a buffer member at a side of the transfer rail configured to temporarily receive the substrates loaded by the loading members, a first wafer supply unit configured to supply a first wafer including semiconductor chips, and/or a bonding unit configured to bond the semiconductor chips to the substrates.

An apparatus for bonding semiconductor chips may comprise transfer rails configured to transfer substrates, loading members configured to load the substrates onto the transfer rails, unloading members configured to unload the substrates from the transfer rails, a first wafer supply unit configured to supply a first wafer including semiconductor chips, and/or a bonding unit configured to bond the semiconductor chips to the substrates. An apparatus for bonding semiconductor chips may comprise a transfer rail configured to transfer substrates, loading members configured to load the substrates onto the transfer rail, unloading members configured to unload the substrates from the transfer rail, a buffer member at a side of the transfer rail configured to temporarily receive the substrates loaded by the loading members, a first wafer supply unit configured to supply a first wafer including semiconductor chips, and/or a bonding unit configured to bond the semiconductor chips to the substrates.

A micro device transfer head and head array are disclosed. In an embodiment, the micro device transfer head includes a base substrate, a mesa structure with sidewalls, an electrode formed over the mesa structure, and a dielectric layer covering the electrode. A voltage can be applied to the micro device transfer head and head array to pick up a micro device from a carrier substrate and release the micro device onto a receiving substrate.

A method of transferring a micro device and an array of micro devices are disclosed. A carrier substrate carrying a micro device connected to a bonding layer is heated to a temperature below a liquidus temperature of the bonding layer, and a transfer head is heated to a temperature above the liquidus temperature of the bonding layer. Upon contacting the micro device with the transfer head, the heat from the transfer head transfers into the bonding layer to at least partially melt the bonding layer. A voltage applied to the transfer head creates a grip force which picks up the micro device from the carrier substrate.