Abstract: The present disclosure relates to a radio frequency device that includes a transfer device die and a multilayer redistribution structure underneath the transfer device die. The transfer device die includes a device region with a back-end-of-line (BEOL) portion and a front-end-of-line (FEOL) portion over the BEOL portion and a transfer substrate. The FEOL portion includes isolation sections and an active layer surrounded by the isolation sections. A top surface of the device region is planarized. The transfer substrate including a porous silicon (PSi) region resides over the top surface of the device region. Herein, the PSi region has a porosity between 1% and 80%. The multilayer redistribution structure includes a number of bump structures, which are at a bottom of the multilayer redistribution structure and electrically coupled to the FEOL portion of the transfer device die.

Abstract: The present disclosure relates to a radio frequency device that includes a transfer device die and a multilayer redistribution structure underneath the transfer device die. The transfer device die includes a device region with a back-end-of-line (BEOL) portion and a front-end-of-line (FEOL) portion over the BEOL portion and a transfer substrate. The FEOL portion includes isolation sections and an active layer surrounded by the isolation sections. A top surface of the device region is planarized. The transfer substrate including a porous silicon (PSi) region resides over the top surface of the device region. Herein, the PSi region has a porosity between 1% and 80%. The multilayer redistribution structure includes a number of bump structures, which are at a bottom of the multilayer redistribution structure and electrically coupled to the FEOL portion of the transfer device die.

Abstract: The present disclosure relates to a radio frequency device that includes a device region with a back-end-of-line (BEOL) portion and a front-end-of-line (FEOL) portion, first bump structures, a first mold compound, and a second mold compound. The FEOL portion includes an active layer, a contact layer, and isolation sections. Herein, the active layer and the isolation sections reside over the contact layer, and the active layer is surrounded by the isolation sections. The BEOL portion is formed underneath the FEOL portion, and the first bump structures and the first mold compound are formed underneath the BEOL portion. Each first bump structure is partially encapsulated by the first mold compound, and electrically coupled to the FEOL portion via connecting layers within the BEOL portion. The second mold compound resides over the active layer without a silicon material, which has a resistivity between 5 Ohm-cm and 30000 Ohm-cm, in between.

Abstract: The present disclosure relates to a Gallium-Nitride (GaN) based module, which includes a module substrate, a thinned switch die residing over the module substrate, a first mold compound, and a second mold compound. The thinned switch die includes an electrode region, a number of switch interconnects extending from a bottom surface of the electrode region to the module substrate, an aluminium gallium nitride (AlGaN) barrier layer over a top surface of the electrode region, a GaN buffer layer over the AlGaN barrier layer, and a lateral two-dimensional electron gas (2DEG) layer realized at a heterojunction of the AlGaN barrier layer and the GaN buffer layer. The first mold compound resides over the module substrate, surrounds the thinned switch die, and extends above a top surface of the thinned switch die to form an opening over the top surface of the thinned switch die. The second mold compound fills the opening.

Abstract: The present disclosure relates to a radio frequency device that includes a transfer device die and a multilayer redistribution structure underneath the transfer device die. The transfer device die includes a device region with a back-end-of-line (BEOL) portion and a front-end-of-line (FEOL) portion over the BEOL portion and a transfer substrate. The FEOL portion includes isolation sections and an active layer surrounded by the isolation sections. A top surface of the device region is planarized. The transfer substrate resides over the top surface of the device region. Herein, silicon crystal does not exist within the transfer substrate or between the transfer substrate and the active layer. The multilayer redistribution structure includes a number of bump structures, which are at a bottom of the multilayer redistribution structure and electrically coupled to the FEOL portion of the transfer device die.

Abstract: The present disclosure relates to a radio frequency (RF) device that includes a mold device die and a multilayer redistribution structure underneath the mold device die. The mold device die includes a device region with a back-end-of-line (BEOL) portion and a front-end-of-line (FEOL) portion over the BEOL portion, and a first mold compound. The FEOL portion includes an active layer formed from a strained silicon epitaxial layer, in which a lattice constant is greater than 5.461 at a temperature of 300K. The first mold compound resides over the active layer. Herein, silicon crystal does not exist between the first mold compound and the active layer. The multilayer redistribution structure includes a number of bump structures, which are at a bottom of the multilayer redistribution structure and electrically coupled to the FEOL portion of the mold device die.

Abstract: The present disclosure relates to a radio frequency device that includes a device region with a back-end-of-line (BEOL) portion and a front-end-of-line (FEOL) portion, first bump structures, a first mold compound, and a second mold compound. The FEOL portion includes an active layer, a contact layer, and isolation sections. Herein, the active layer and the isolation sections reside over the contact layer, and the active layer is surrounded by the isolation sections. The BEOL portion is formed underneath the FEOL portion, and the first bump structures and the first mold compound are formed underneath the BEOL portion. Each first bump structure is partially encapsulated by the first mold compound, and electrically coupled to the FEOL portion via connecting layers within the BEOL portion. The second mold compound resides over the active layer without a silicon material, which has a resistivity between 5 Ohm-cm and 30000 Ohm-cm, in between.

Abstract: Disclosed is a tunable inductor device having a substrate, a planar spiral conductor having a plurality of spaced-apart turns disposed over the substrate, and a phase change switch (PCS) having a patch of a phase change material (PCM) disposed over the substrate between and in contact with a pair of adjacent segments of the plurality of spaced-apart turns, wherein the patch of the PCM is electrically insulating in an amorphous state and electrically conductive in a crystalline state. The PCS further includes a thermal element disposed adjacent to the patch of PCM, wherein the thermal element is configured to maintain the patch of the PCM to within a first temperature range until the patch of the PCM converts to the amorphous state and maintain the patch of the PCM within a second temperature range until the first patch of PCM converts to the crystalline state.

Abstract: The present disclosure relates to a radio frequency device that includes a transfer device die and a multilayer redistribution structure underneath the transfer device die. The transfer device die includes a device region with a back-end-of-line (BEOL) portion and a front-end-of-line (FEOL) portion over the BEOL portion and a transfer substrate. The FEOL portion includes isolation sections and an active layer surrounded by the isolation sections. A top surface of the device region is planarized. The transfer substrate including a porous silicon (PSi) region resides over the top surface of the device region. Herein, the PSi region has a porosity between 1% and 80%. The multilayer redistribution structure includes a number of bump structures, which are at a bottom of the multilayer redistribution structure and electrically coupled to the FEOL portion of the transfer device die.

Abstract: Disclosed is a reconfigurable transistor device having a substrate, a plurality of first transistor fingers disposed in a first region over the substrate, and a phase change switch (PCS) having a patch of a phase change material (PCM) disposed over the substrate in a second region to selectively couple a first set of the plurality of first transistor fingers to a bus, wherein the patch of the PCM is electrically insulating in an amorphous state and electrically conductive in a crystalline state. The PCS further includes a thermal element disposed adjacent to the patch of PCM, wherein the first thermal element is configured to maintain the patch of the PCM to within a first temperature range until the patch of the PCM converts to the amorphous state and maintain the patch of the PCM within a second temperature range until the first patch of PCM converts to the crystalline state.

Abstract: The present disclosure relates to a Gallium-Nitride (GaN) based module, which includes a module substrate, a thinned switch die residing over the module substrate, a first mold compound, and a second mold compound. The thinned switch die includes an electrode region, a number of switch interconnects extending from a bottom surface of the electrode region to the module substrate, an aluminium gallium nitride (AlGaN) barrier layer over a top surface of the electrode region, a GaN buffer layer over the AlGaN barrier layer, and a lateral two-dimensional electron gas (2DEG) layer realized at a heterojunction of the AlGaN barrier layer and the GaN buffer layer. The first mold compound resides over the module substrate, surrounds the thinned switch die, and extends above a top surface of the thinned switch die to form an opening over the top surface of the thinned switch die. The second mold compound fills the opening.

Abstract: The present disclosure relates to a radio frequency device that includes a transfer device die and a multilayer redistribution structure underneath the transfer device die. The transfer device die includes a device region with a back-end-of-line (BEOL) portion and a front-end-of-line (FEOL) portion over the BEOL portion and a transfer substrate. The FEOL portion includes isolation sections and an active layer surrounded by the isolation sections. A top surface of the device region is planarized. The transfer substrate resides over the top surface of the device region. Herein, silicon crystal does not exist within the transfer substrate or between the transfer substrate and the active layer. The multilayer redistribution structure includes a number of bump structures, which are at a bottom of the multilayer redistribution structure and electrically coupled to the FEOL portion of the transfer device die.

Abstract: The present disclosure relates to a radio frequency device that includes a transfer device die and a multilayer redistribution structure underneath the transfer device die. The transfer device die includes a device region with a back-end-of-line (BEOL) portion and a front-end-of-line (FEOL) portion over the BEOL portion and a transfer substrate. The FEOL portion includes isolation sections and an active layer surrounded by the isolation sections. A top surface of the device region is planarized. The transfer substrate including a porous silicon (PSi) region resides over the top surface of the device region. Herein, the PSi region has a porosity between 1% and 80%. The multilayer redistribution structure includes a number of bump structures, which are at a bottom of the multilayer redistribution structure and electrically coupled to the FEOL portion of the transfer device die.

Abstract: The present disclosure relates to a thermally enhanced package, which includes a carrier, a thinned die over the carrier, a mold compound, and a heat extractor. The thinned die includes a device layer over the carrier and a dielectric layer over the device layer. The mold compound resides over the carrier, surrounds the thinned die, and extends beyond a top surface of the thinned die to define an opening within the mold compound and over the thinned die. The top surface of the thinned die is at a bottom of the opening. At least a portion of the heat extractor is inserted into the opening and in thermal contact with the thinned die. Herein the heat extractor is formed of a metal or an alloy.

Abstract: The present disclosure relates to a radio frequency (RF) device including a device substrate, a thinned device die with a device region over the device substrate, a first mold compound, and a second mold compound. The device region includes an isolation portion, a back-end-of-line (BEOL) portion, and a front-end-of-line (FEOL) portion with a contact layer and an active section. The contact layer resides over the BEOL portion, the active section resides over the contact layer, and the isolation portion resides over the contact layer to encapsulate the active section. The first mold compound resides over the device substrate, surrounds the thinned device die, and extends vertically beyond the thinned device die to define an opening over the thinned device die and within the first mold compound. The second mold compound fills the opening and directly connects the isolation portion of the thinned device die.

Abstract: The present disclosure relates to a radio frequency (RF) device and a process for making the same. According to the process, a precursor wafer, which includes device regions, individual interfacial layers, individual p-type doped layers, and a silicon handle substrate, is firstly provided. Each individual interfacial layer is over an active layer of a corresponding device region, each individual p-type doped layer is over a corresponding individual interfacial layer, and the silicon handle substrate is over each individual p-type doped layer. Herein, each individual interfacial layer is formed of SiGe, and each individual p-type doped layer is a silicon layer doped with a p-type material that has a doped concentration greater than 1E18cm-3. Next, the silicon handle substrate is completely removed to provide an etched wafer, and each individual p-type doped layer is completely removed from the etched wafer.

Abstract: The present disclosure relates to a radio frequency device that includes a transfer device die and a multilayer redistribution structure underneath the transfer device die. The transfer device die includes a device region with a back-end-of-line (BEOL) portion and a front-end-of-line (FEOL) portion over the BEOL portion and a transfer substrate. The FEOL portion includes isolation sections and an active layer surrounded by the isolation sections. A top surface of the device region is planarized. The transfer substrate including a porous silicon (PSi) region resides over the top surface of the device region. Herein, the PSi region has a porosity between 1% and 80%. The multilayer redistribution structure includes a number of bump structures, which are at a bottom of the multilayer redistribution structure and electrically coupled to the FEOL portion of the transfer device die.

Abstract: The present disclosure relates to a radio frequency (RF) device and a process for making the same. According to the process, a precursor wafer, which includes device regions, individual interfacial layers, individual p-type doped layers, and a silicon handle substrate, is firstly provided. Each individual interfacial layer is over an active layer of a corresponding device region, each individual p-type doped layer is over a corresponding individual interfacial layer, and the silicon handle substrate is over each individual p-type doped layer. Herein, each individual interfacial layer is formed of SiGe, and each individual p-type doped layer is a silicon layer doped with a p-type material that has a doped concentration greater than 1E18cm-3. Next, the silicon handle substrate is completely removed to provide an etched wafer, and each individual p-type doped layer is completely removed from the etched wafer.

Abstract: The present disclosure relates to a thermally enhanced package, which includes a carrier, a thinned die over the carrier, a mold compound, and a heat extractor. The thinned die includes a device layer over the carrier and a dielectric layer over the device layer. The mold compound resides over the carrier, surrounds the thinned die, and extends beyond a top surface of the thinned die to define an opening within the mold compound and over the thinned die. The top surface of the thinned die is at a bottom of the opening. At least a portion of the heat extractor is inserted into the opening and in thermal contact with the thinned die. Herein the heat extractor is formed of a metal or an alloy.

Abstract: The present disclosure relates to a radio frequency (RF) device that includes a mold device die and a multilayer redistribution structure underneath the mold device die. The mold device die includes a device region with a back-end-of-line (BEOL) portion and a front-end-of-line (FEOL) portion over the BEOL portion, and a first mold compound. The FEOL portion includes an active layer formed from a strained silicon epitaxial layer, in which a lattice constant is greater than 5.461 at a temperature of 300K. The first mold compound resides over the active layer. Herein, silicon crystal does not exist between the first mold compound and the active layer. The multilayer redistribution structure includes a number of bump structures, which are at a bottom of the multilayer redistribution structure and electrically coupled to the FEOL portion of the mold device die.