Various embodiments of the present application are directed towards a method for forming an integrated chip in which a group III-V device is bonded to a substrate, as well as the resulting integrated chip. In some embodiments, the method includes: forming a chip including an epitaxial stack, a metal structure on the epitaxial stack, and a diffusion layer between the metal structure and the epitaxial stack; bonding the chip to a substrate so the metal structure is between the substrate and the epitaxial stack; and performing an etch into the epitaxial stack to form a mesa structure with sidewalls spaced from sidewalls of the diffusion layer. The metal structure may, for example, be a metal bump patterned before the bonding or may, for example, be a metal layer that is on an etch stop layer and that protrudes through the etch stop layer to the diffusion layer.

Transistors including semiconductor regions where operating current flows are provided above a substrate. Operating electrodes of conductive material having thermal conductivity higher than the semiconductor regions and contacting the semiconductor regions to conduct operating current to the semiconductor regions are disposed. A conductor pillar for external connection contains contact regions where the semiconductor regions and the operating electrodes contact, and is electrically connected to the operating electrodes. The contact regions are disposed in a first direction. Each contact region has a planar shape long in a second direction orthogonal to the first direction. A first average distance, obtained by averaging distances in the second direction from each end portion of the contact region in the second direction to an edge of the conductor pillar across the contact regions, exceeds an average distance value in a height direction from the contact region to a top surface of the conductor pillar.

A circuit element is formed on a substrate made of a compound semiconductor. A bonding pad is disposed on the circuit element so as to at least partially overlap the circuit element. The bonding pad includes a first metal film and a second metal film formed on the first metal film. A metal material of the second metal film has a higher Young's modulus than a metal material of the first metal film.

In some embodiments, a device includes a thermal-electrical-mechanical (TEM) chip having a functional circuit, a first die attached to a first side of the TEM chip, and a first via on the first side of the TEM chip and adjacent to the first die, the first via being electrically coupled to the TEM chip. The device also includes a first molding layer surrounding the TEM chip, the first die and the first via, where an upper surface of the first die and an upper surface of the first via are level with an upper surface of the first molding layer. The device further includes a first redistribution layer over the upper surface of the first molding layer and electrically coupled to the first via and the first die.

A photodiode (PD) device that monolithically integrates a PD element with a waveguide element is disclosed. The PD device includes a conducting layer with a first region and a second region next to the first region, where the PD element exists in the first region, while, the waveguide element exists in the second region and optically couples with the PD element. The waveguide element includes a core layer and a cladding layer on the conducting layer, which forms an optical confinement structure. The PD element includes an absorption layer on the conducting layer and a p-type cladding layer on the absorption layer, which form another optical confinement structure. The absorption layer has a length at least 12 m measured from the interface against the core layer.

Various embodiments of the present application are directed towards a method for forming an integrated chip in which a group III-V device is bonded to a substrate, as well as the resulting integrated chip. In some embodiments, the method includes: forming a chip including an epitaxial stack, a metal structure on the epitaxial stack, and a diffusion layer between the metal structure and the epitaxial stack; bonding the chip to a substrate so the metal structure is between the substrate and the epitaxial stack; and performing an etch into the epitaxial stack to form a mesa structure with sidewalls spaced from sidewalls of the diffusion layer. The metal structure may, for example, be a metal bump patterned before the bonding or may, for example, be a metal layer that is on an etch stop layer and that protrudes through the etch stop layer to the diffusion layer.

A multi-clip structure includes a first clip for die bonding and a second clip for die bonding. The multi-clip structure further includes a retaining tape fixed to the first clip and to the second clip to hold the first clip and the second clip together.

A circuit element is formed on a substrate made of a compound semiconductor. A bonding pad is disposed on the circuit element so as to at least partially overlap the circuit element. The bonding pad includes a first metal film and a second metal film formed on the first metal film. A metal material of the second metal film has a higher Young's modulus than a metal material of the first metal film.

A structure includes a metal pad, a passivation layer having a portion covering edge portions of the metal pad, and a dummy metal plate over the passivation layer. The dummy metal plate has a plurality of through-openings therein. The dummy metal plate has a zigzagged edge. A dielectric layer has a first portion overlying the dummy metal plate, second portions filling the first plurality of through-openings, and a third portion contacting the first zigzagged edge.

A photodiode (PD) device that monolithically integrates a PD element with a waveguide element is disclosed. The PD device includes a conducting layer with a first region and a second region next to the first region, where the PD element exists in the first region, while, the waveguide element exists in the second region and optically couples with the PD element. The waveguide element includes a core layer and a cladding layer on the conducting layer, which forms an optical confinement structure. The PD element includes an absorption layer on the conducting layer and a p-type cladding layer on the absorption layer, which form another optical confinement structure. The absorption layer has a length at least 12 m measured from the interface against the core layer.