Abstract: A semiconductor structure is provided. The semiconductor structure includes a substrate having a front side and a back side opposite the front side. The semiconductor structure also includes a first contact metal layer disposed on the front side of the substrate. The semiconductor structure further includes a III-V compound semiconductor layer disposed between the substrate and the first contact metal layer. Moreover, the semiconductor structure includes a via hole penetrating through the substrate and the III-V compound semiconductor layer from the back side of the substrate. The bottom of the via hole is defined by the first contact metal layer, and the first contact metal layer includes molybdenum, tungsten, iridium, palladium, platinum, cobalt, ruthenium, osmium, rhodium, rhenium, or a combination thereof.

Abstract: A semiconductor chip includes an active device and a passive device formed over a substrate. A passivation layer covers the active device and the passive device. A barrier structure surrounds the active device. A ceiling layer is formed across the barrier structure over the active device. The ceiling layer has an opening exposing the barrier structure.

Abstract: A transistor device includes a substrate and a gate structure. The gate structure is disposed on the substrate. The gate structure includes a first metal layer and a refractory metal layer disposed on the first metal layer, wherein the first metal layer is disconnected and the refractory metal layer is disconnected.

Abstract: A semiconductor structure is provided. The semiconductor structure includes a substrate having a front side and a back side opposite the front side. The semiconductor structure also includes a first contact metal layer disposed on the front side of the substrate. The semiconductor structure further includes a III-V compound semiconductor layer disposed between the substrate and the first contact metal layer. Moreover, the semiconductor structure includes a via hole penetrating through the substrate and the III-V compound semiconductor layer from the back side of the substrate. The bottom of the via hole is defined by the first contact metal layer, and the first contact metal layer includes molybdenum, tungsten, iridium, palladium, platinum, cobalt, ruthenium, osmium, rhodium, rhenium, or a combination thereof.

Abstract: A gate-sinking pseudomorphic high electron mobility transistor comprises a compound semiconductor substrate overlaid with an epitaxial structure which includes sequentially a buffer layer, a channel layer, a Schottky layer, and a first cap layer. The Schottky layer comprises from bottom to top at least two stacked regions of semiconductor material. Each of the two adjacent stacked regions differs in material from the other and provides a stacked region contact interface therebetween. In any two adjacent stacked regions of the Schottky layer, one stacked region composed of AlGaAs-based semiconductor material alternates with the other stacked region composed of InGaP-based semiconductor material. A gate-sinking region is beneath the first gate metal layer of the gate electrode, and the bottom boundary of the gate-sinking region is located at the one of the at least one stacked region contact interface of the Schottky layer.

Abstract: A gate-sinking pseudomorphic high electron mobility transistor comprises a compound semiconductor substrate overlaid with an epitaxial structure which includes sequentially a buffer layer, a channel layer, a Schottky layer, and a first cap layer. The Schottky layer comprises from bottom to top at least two stacked regions of semiconductor material. Each of the two adjacent stacked regions differs in material from the other and provides a stacked region contact interface therebetween. In any two adjacent stacked regions of the Schottky layer, one stacked region composed of AlGaAs-based semiconductor material alternates with the other stacked region composed of InGaP-based semiconductor material. A gate-sinking region is beneath the first gate metal layer of the gate electrode, and the bottom boundary of the gate-sinking region is located at the one of the at least one stacked region contact interface of the Schottky layer.

Abstract: A semiconductor integrated circuit comprises a semiconductor substrate having a via-hole, a front-side-metal layer formed on a top surface of the semiconductor substrate, a seed-metal layer and a backside-metal layer. A bottom surface of an inner surface of the via-hole is at least partially defined by the front-side-metal layer. A surrounding surface of the inner surface of the via-hole is at least partially defined by the semiconductor substrate. The seed-metal layer is formed on the inner surface of the via-hole and a bottom surface of the semiconductor substrate such that the seed-metal layer and the front-side-metal layer are connected. The backside-metal layer is formed on an outer surface of the seed-metal layer. An aspect ratio of the via-hole is greater than or equal to 0.2 and less than or equal to 3, thereby a thickness uniformity of the backside-metal layer is improved.

Abstract: An ohmic metal for GaN device comprises a diffusion barrier seed metal layer and a plurality of metal layers. The diffusion barrier seed metal layer is formed on an epitaxial structure layer. The diffusion barrier seed metal layer is made of Pt. The epitaxial structure layer is made of AlGaN or GaN. The plurality of metal layers is formed on the diffusion barrier seed metal layer. The plurality of metal layers comprises a first metal layer and a second metal layer. The first metal layer is formed on the diffusion barrier seed metal layer. The first metal layer is made of Ti. The second metal layer is formed on the first metal layer. The second metal layer is made of Al. By the diffusion barrier seed metal layer, so as to suppress the diffusion of the plurality of metal layers into the epitaxial structure layer.

Abstract: An improved structure for reducing compound semiconductor wafer distortion comprises a contact metal layer and at least one stress balance layer. The contact metal layer is formed on a bottom surface of a compound semiconductor wafer; the at least one stress balance layer is formed on a bottom surface of the contact metal layer, wherein a thermal conductivity of the at least one stress balance layer is greater than or equal to 10 W/m-K. The stress suffered by the compound semiconductor wafer is balanced by the at least one stress balance layer, so that the distortion of the compound semiconductor wafer is reduced.

Abstract: An improved high temperature resistant backside metallization for compound semiconductors comprises a front-side metal layer formed on a compound semiconductor substrate; at least one via hole penetrating the compound semiconductor substrate, a top of an inner surface of the via hole is defined by the front-side metal layer; at least one seed metal layer, at least one backside metal layer and at least one diffusion barrier layer sequentially formed on a bottom surface of the compound semiconductor substrate and the inner surface of the via hole, the seed metal layer and the front-side metal layer are electrically connected through the via hole; a die attachment metal layer formed on a bottom surface of the diffusion barrier layer other than the via hole and an adjacent area near the via hole. The diffusion barrier layer prevents the backside metal layer from diffusing into the die attachment metal layer.

Abstract: An ohmic metal for GaN device comprises a diffusion barrier seed metal layer and a plurality of metal layers. The diffusion barrier seed metal layer is formed on an epitaxial structure layer. The diffusion barrier seed metal layer is made of Pt. The epitaxial structure layer is made of AlGaN or GaN. The plurality of metal layers is formed on the diffusion barrier seed metal layer. The plurality of metal layers comprises a first metal layer and a second metal layer. The first metal layer is formed on the diffusion barrier seed metal layer. The first metal layer is made of Ti. The second metal layer is formed on the first metal layer. The second metal layer is made of Al. By the diffusion barrier seed metal layer, so as to suppress the diffusion of the plurality of metal layers into the epitaxial structure layer.

Abstract: An improved high temperature resistant backside metallization for compound semiconductors comprises a front-side metal layer formed on a compound semiconductor substrate; at least one via hole penetrating the compound semiconductor substrate, a top of an inner surface of the via hole is defined by the front-side metal layer; at least one seed metal layer, at least one backside metal layer and at least one diffusion barrier layer sequentially formed on a bottom surface of the compound semiconductor substrate and the inner surface of the via hole, the seed metal layer and the front-side metal layer are electrically connected through the via hole; a die attachment metal layer formed on a bottom surface of the diffusion barrier layer other than the via hole and an adjacent area near the via hole. The diffusion barrier layer prevents the backside metal layer from diffusing into the die attachment metal layer.

Abstract: An improved structure for reducing compound semiconductor wafer distortion comprises a contact metal layer, at least one stress balance layer and a die attachment layer. The contact metal layer is formed on a bottom surface of a compound semiconductor wafer; the at least one stress balance layer is formed on a bottom surface of the contact metal layer, wherein the at least one stress balance layer is made of at least one conductive material; the die attachment layer is formed on a bottom surface of the at least one stress balance layer, wherein the die attachment layer is made of conductive material. By locating the at least one stress balance layer between the contact metal layer and the die attachment layer, the stress suffered by the compound semiconductor wafer is balanced so that the distortion of the compound semiconductor wafer is reduced.

Abstract: An improved structure for reducing compound semiconductor wafer distortion comprises a contact metal layer formed on a bottom surface of a compound semiconductor wafer, at least one stress balance layer formed on a bottom surface of the contact metal layer and made of nonconductive material, stress balance layer via holes and a die attachment layer. Each stress balance layer via hole penetrates the stress balance layer. The die attachment layer is made of conductive material, formed on a bottom surface of the stress balance layer and an inner surface of each stress balance layer via hole, and electrically connected with the contact metal layer through the stress balance layer via holes. By locating the stress balance layer between the contact metal layer and the die attachment layer, the stress suffered by the compound semiconductor wafer is balanced so that the distortion of the compound semiconductor wafer is reduced.

Abstract: An improved structure for reducing compound semiconductor wafer distortion comprises a contact metal layer and at least one stress balance layer. The contact metal layer is formed on a bottom surface of a compound semiconductor wafer; the at least one stress balance layer is formed on a bottom surface of the contact metal layer, wherein a thermal conductivity of the at least one stress balance layer is greater than or equal to 10 W/m-K. The stress suffered by the compound semiconductor wafer is balanced by the at least one stress balance layer, so that the distortion of the compound semiconductor wafer is reduced.

Abstract: An improved structure for reducing compound semiconductor wafer distortion comprises a contact metal layer, at least one stress balance layer and a die attachment layer. The contact metal layer is formed on a bottom surface of a compound semiconductor wafer; the at least one stress balance layer is formed on a bottom surface of the contact metal layer, wherein the at least one stress balance layer is made of at least one conductive material; the die attachment layer is formed on a bottom surface of the at least one stress balance layer, wherein the die attachment layer is made of conductive material. By locating the at least one stress balance layer between the contact metal layer and the die attachment layer, the stress suffered by the compound semiconductor wafer is balanced so that the distortion of the compound semiconductor wafer is reduced.

Abstract: The present invention relates to a compound semiconductor integrated circuit chip having a front and/or back surface metal layer used for electrical connection to an external circuit. The compound semiconductor integrated circuit chip (first chip) comprises a substrate, an electronic device layer, and a dielectric layer. A first metal layer is formed on the front side of the dielectric layer, and a third metal layer is formed on the back side of the substrate. The first and third metal layer are made essentially of Cu and used for the connection to other electronic circuits. A second chip may be mounted on the first chip with electrical connection made with the first or the third metal layer that extends over the electronic device in the first chip in the three-dimensional manner to make the electrical connection between the two chips having connection nodes away from each other.

Abstract: An advanced moisture resistant structure of compound semiconductor integrated circuit comprises a compound semiconductor substrate, a compound semiconductor epitaxial structure, a compound semiconductor integrated circuit and a moisture barrier layer. The compound semiconductor epitaxial structure is formed on the compound semiconductor substrate. The compound semiconductor integrated circuit is foimed on the compound semiconductor epitaxial structure. The moisture barrier layer is formed on the compound semiconductor integrated circuit. The moisture barrier layer is made of A12O3. The thickness of the moisture barrier layer is greater than or equal to 400 ? and less than or equal to 1000 ? so as to enhance the moisture resistant ability of the compound semiconductor integrated circuit.

Abstract: An improved gate metal structure for compound semiconductor devices comprises sequentially a compound semiconductor substrate, a Schottky barrier layer, an insulating layer and a gate metal. The insulating layer has a gate recess. The surrounding and the bottom of the gate recess are defined by the insulating layer and the Schottky barrier layer respectively. The gate metal includes a contact layer formed on the insulating layer, covering the gate recess and contacted with the Schottky barrier layer at the bottom of the gate recess; a first diffusion barrier layer formed on the contact layer; a second diffusion barrier layer formed on the first diffusion barrier layer; and a conduct layer formed on the second diffusion barrier layer. Thereby the reliability of the compound semiconductor devices is enhanced.

Abstract: A stacked structure comprises a semiconductor chip which includes a substrate having at least one substrate via hole penetrating through the substrate; at least one backside metal layer formed on a backside of the substrate covering an inner surface of the substrate via hole and at least part of the backside of the substrate; at least one front-side metal layer formed on the front-side of the substrate and electrically connected to the at least one backside metal layer on a top of at least one of the at least one substrate via hole; at least one electronic device formed on the front-side of the substrate and electrically connected to the at least one front-side metal layer; and at least one metal bump formed on at least one of the backside metal layer and the front-side metal layer.