| Patent application number | Description | Published |
| 20080258213 | Shielded Gate Field Effect Transistor - A FET includes a trench in a semiconductor region. The trench has a lower portion with a shield electrode therein, and an upper portion with a gate electrode therein, where the upper portion is wider than the lower portion. The semiconductor region includes a substrate of a first conductivity type and a first silicon region of a second conductivity type over the substrate. The first silicon region has a first portion extending to a depth intermediate top and bottom surfaces of the gate electrode. The first silicon region has a second portion extending to a depth intermediate top and bottom surfaces of the shield electrode. The semiconductor region further includes a second silicon region of the first conductivity type between the lower trench portion and the second portion of the first silicon region that has a laterally-graded doping concentration decreasing in a direction away from the sidewalls of the lower trench portion. | 10-23-2008 |
| 20090111227 | Method for Forming Trench Gate Field Effect Transistor with Recessed Mesas Using Spacers - A method for forming a field effect transistor with an active area and a termination region surrounding the active area includes forming a well region in a first silicon region, where the well region and the first silicon region are of opposite conductivity type. Gate trenches extending through the well region and terminating within the first silicon region are formed. A recessed gate is formed in each gate trench. A dielectric cap is formed over each recessed gate. The well region is recessed between adjacent trenches to expose upper sidewalls of each dielectric cap. A blanket source implant is carried out to form a second silicon region in an upper portion of the recessed well region between every two adjacent trenches. A dielectric spacer is formed along each exposed upper sidewall of the dielectric cap, with every two adjacent dielectric spacers located between every two adjacent gate trenches forming an opening over the second silicon region. The second silicon region is recessed through the opening between every two adjacent dielectric spacers so that only portions of the second silicon region directly below the dielectric spacers remain. The remaining portions of the second silicon region form source regions. | 04-30-2009 |
| 20090173993 | Structure and Method of Forming a Topside Contact to a Backside Terminal of a Semiconductor Device - A vertically conducting semiconductor device includes a semiconductor substrate having a topside surface and a backside surface. The semiconductor substrate serves as a terminal of the vertically conducting device for biasing the vertically conducting device during operation. An epitaxial layer extends over the topside surface of the semiconductor substrate but terminates prior to reaching an edge of the semiconductor substrate so as to form a recessed region along a periphery of the semiconductor substrate. An interconnect layer extends into the recessed region but terminates prior to reaching an edge of the semiconductor substrate. The interconnect layer electrically contacts the topside surface of the semiconductor substrate in the recessed region to thereby provide a topside contact to the semiconductor substrate. | 07-09-2009 |
| 20090181520 | Method and Structure for Dividing a Substrate into Individual Devices - A method for obtaining individual dies from a semiconductor structure is disclosed. The semiconductor structure includes a device layer, and the device layer in turn includes active regions separated by predefined spacings. Thick metal is selectively formed on backside of the device layer such that thick metal is formed on backside of active regions but not on backside of the predefined spacings. The semiconductor structure is then cut along the predefined spacings to separate the active regions with thick metal on their backside into individual dies. | 07-16-2009 |
| 20090191678 | Method of Forming a Shielded Gate Field Effect Transistor - A semiconductor region with an epitaxial layer extending over the semiconductor region is provided. A first silicon etch is performed to form an upper trench portion extending into and terminating within the epitaxial layer. A protective material is formed extending along sidewalls of the upper trench portion and over mesa regions adjacent the upper trench portion but not along a bottom surface of the upper trench portion. A second silicon etch is performed to form a lower trench portion extending from the bottom surface of the upper trench portion through the epitaxial layer and terminating within the semiconductor region, such that the lower trench portion is narrower than the upper trench portion. A two-pass angled implant of dopants of the first conductivity type is carried out to form a silicon region of first conductivity type along sidewalls of the lower trench portion, while the protective material blocks the implant dopants from entering the sidewalls of the upper trench portion and the mesa region adjacent the upper trench portion. | 07-30-2009 |
| 20090200606 | Power Device Edge Termination Having a Resistor with One End Biased to Source Voltage - A field effect transistor (FET) includes a source electrode for receiving an externally-provided source voltage. The FET further includes an active region and a termination region surrounding the active region. A resistive element is coupled to the termination region, wherein upon occurrence of avalanche breakdown in the termination region an avalanche current starts to flow in the termination region, and the resistive element is configured to induce a portion of the avalanche current to flow through the termination region and a remaining portion of the avalanche current to flow through the active region. During operation, one end of the resistive element is biased to the source voltage. | 08-13-2009 |
| 20090230465 | Trench-Gate Field Effect Transistors and Methods of Forming the Same - A field effect transistor includes a body region of a first conductivity type over a semiconductor region of a second conductivity type. A gate trench extends through the body region and terminates within the semiconductor region. At least one conductive shield electrode is disposed in the gate trench. A gate electrode is disposed in the gate trench over but insulated from the at least one conductive shield electrode. A shield dielectric layer insulates the at lease one conductive shield electrode from the semiconductor region. A gate dielectric layer insulates the gate electrode from the body region. The shield dielectric layer is formed such that it flares out and extends directly under the body region. | 09-17-2009 |
| 20090261461 | SEMICONDUCTOR PACKAGE WITH LEAD INTRUSIONS - Semiconductor packages comprising a plurality of lead fingers containing a lead intrusion at the edge of the lead fingers are described. The semiconductor packages comprise an integrated circuit chip that is connected to a die pad and is electrically connected to multiple lead fingers. One or more of the lead fingers may have a lead intrusion disposed on the external exposed lower surface of the lead finger. The lead intrusion may have a height that is about ⅕ to about ½ the height of a lead finger, a width that is about ⅕ to about 1/2 the width of a lead finger, and a depth that is about ¼ to about ¾ the length of the externally exposed lower surface of a lead finger. The lead intrusion increases the area on the lead finger that contacts a bond material, such as solder, and therefore increase the strength of the joint between the semiconductor package and an external surface to which the lead finger is connected (i.e., a PCB). The lead intrusion allows out gassing during reflow of the bond material which may reduce voiding. The lead intrusion can also increase bond joint reliability by providing longer crack propagation length. | 10-22-2009 |
| 20100022059 | Method of fabricating high voltage semiconductor devices with JFET regions containing dielectrically isolated junctions - A high-voltage field-effect device contains an extended drain or “drift” region having a plurality of JFET regions separated by portions of the drift region. Each of the JFET regions is filled with material of an opposite conductivity type to that of the drift region, and at least two sides of each JFET region is lined with an oxide layer. In one group of embodiments the JFET regions extend from the surface of an epitaxial layer to an interface between the epitaxial layer and an underlying substrate, and the walls of each JFET region are lined with an oxide layer. When the device is blocking a voltage in the off condition, the semiconductor material inside the JFET regions and in the drift region that separates the JFET regions is depleted. This improves the voltage-blocking ability of the device while conserving chip area. The oxide layer prevents dopant from the JFET regions from diffusing into the drift region and allowing the JFET regions to be accurately located in the drift region. | 01-28-2010 |
| 20100038708 | Method and Structure for Forming a Shielded Gate Field Effect Transistor - A method of forming a charge balance MOSFET includes the following steps. A substrate with an overlying epitaxial layer both of a first conductivity type, are provided. A gate trench extending through the epitaxial layer and terminating within the substrate is formed. A shield dielectric lining sidewalls and bottom surface of the gate trench is formed. A shield electrode is formed in the gate trench. A gate dielectric layer is formed along upper sidewalls of the gate trench. A gate electrode is formed in the gate trench such that the gate electrode extends over but is insulated from the shield electrode. A deep dimple extending through the epitaxial layer and terminating within the substrate is formed such that the deep dimple is laterally spaced from the gate trench. The deep dimple is filled with silicon material of the second conductivity type. | 02-18-2010 |
| 20100163846 | Nano-tube mosfet technology and devices - This invention discloses a semiconductor power device disposed in a semiconductor substrate and the semiconductor substrate has a plurality of trenches. Each of the trenches is filled with a plurality of epitaxial layers of alternating conductivity types constituting nano tubes functioning as conducting channels stacked as layers extending along a sidewall direction with a “Gap Filler” layer filling a merging-gap between the nano tubes disposed substantially at a center of each of the trenches. The “Gap Filler” layer can be very lightly doped Silicon or grown and deposited dielectric layer. In an exemplary embodiment, the plurality of trenches are separated by pillar columns each having a width approximately half to one-third of a width of the trenches. | 07-01-2010 |
| 20100258855 | Field Effect Transistor with Self-aligned Source and Heavy Body Regions and Method of Manufacturing Same - A field effect transistor includes a plurality of trenches extending into a semiconductor region of a first conductivity type. The plurality of trenches include a plurality of gated trenches and a plurality of non-gated trenches. A body region of a second conductivity extends in the semiconductor region between adjacent trenches. A dielectric material fills a bottom portion of each of the gated and non-gated trenches. A gate electrode is disposed in each gated trench. A conductive material of the second conductivity type is disposed in each non-gated trench such that the conductive material and contacts corresponding body regions along sidewalls of the non-gated trench. | 10-14-2010 |
| 20100258862 | TRENCH-GATE FIELD EFFECT TRANSISTOR WITH CHANNEL ENHANCEMENT REGION AND METHODS OF FORMING THE SAME - A field effect transistor includes a body region of a first conductivity type in a semiconductor region of a second conductivity type. A gate trench extends through the body region and terminating within the semiconductor region. A source region of the second conductivity type extends in the body region adjacent the gate trench. The source region and an interface between the body region and the semiconductor region define a channel region therebetween which extends along the gate trench sidewall. A channel enhancement region of the second conductivity type is formed adjacent the gate trench. The channel enhancement region partially extends into a lower portion of the channel region to thereby reduce a resistance of the channel region. | 10-14-2010 |
| 20100267200 | SEMICONDUCTOR DIE PACKAGES USING THIN DIES AND METAL SUBSTRATES - A semiconductor die package is disclosed. The semiconductor die package comprises a metal substrate, and a semiconductor die comprising a first surface comprising a first electrical terminal, a second surface including a second electrical terminal, and at least one aperture. The metal substrate is attached to the second surface. A plurality of conductive structures is on the semiconductor die, and includes at least one conductive structure disposed in the at least one aperture. Other conductive structures may be disposed on the first surface of the semiconductor die. | 10-21-2010 |
| 20100314659 | Nanotube Semiconductor Devices - A semiconductor device includes a first semiconductor layer and a second semiconductor layer of opposite conductivity type, a first epitaxial layer of the first conductivity type formed on sidewalls of the trenches, and a second epitaxial layer of the second conductivity type formed on the first epitaxial layer where the second epitaxial layer is electrically connected to the second semiconductor layer. The first epitaxial layer and the second epitaxial layer form parallel doped regions along the sidewalls of the trenches, each having uniform doping concentration. The second epitaxial layer has a first thickness and a first doping concentration and the first epitaxial layer and a mesa of the first semiconductor layer together having a second thickness and a second average doping concentration where the first and second thicknesses and the first doping concentration and second average doping concentrations are selected to achieve charge balance in operation. | 12-16-2010 |
| 20100314682 | Configurations and methods for manufacturing devices with trench-oxide-nano-tube super-junctions - This invention discloses semiconductor power device disposed on a semiconductor substrate of a first conductivity type. The semiconductor substrate supports an epitaxial layer of a second conductivity type thereon wherein the semiconductor power device is supported on a super-junction structure. The super-junction structure comprises a plurality of trenches opened from a top surface in the epitaxial layer; wherein each of the trenches having trench sidewalls covered with a first epitaxial layer of the first conductivity type to counter charge the epitaxial layer of the second conductivity type. A second epitaxial layer may be grown over the first epitaxial layer. Each of the trenches is filled with a non-doped dielectric material in a remaining trench gap space. Each of the trench sidewalls is opened with a tilted angle to form converging U-shaped trenches. | 12-16-2010 |
| 20100317158 | Method for Forming Nanotube Semiconductor Devices - A method for forming a semiconductor device includes forming a nanotube region using a thin epitaxial layer formed on the sidewall of a trench in the semiconductor body. The thin epitaxial layer has uniform doping concentration. In another embodiment, a first thin epitaxial layer of the same conductivity type as the semiconductor body is formed on the sidewall of a trench in the semiconductor body and a second thin epitaxial layer of the opposite conductivity type is formed on the first epitaxial layer. The first and second epitaxial layers have uniform doping concentration. The thickness and doping concentrations of the first and second epitaxial layers and the semiconductor body are selected to achieve charge balance. In one embodiment, the semiconductor body is a lightly doped P-type substrate. A vertical trench MOSFET, an IGBT, a Schottky diode and a P-N junction diode can be formed using the same N-Epi/P-Epi nanotube structure. | 12-16-2010 |
| 20110003439 | SEMICONDUCTOR DEVICE PACKAGE HAVING FEATURES FORMED BY ELECTROPLATING - Embodiments in accordance with the present invention relate to the fabrication of packages for semiconductor devices, and in particular to the use of electroplating techniques to form features on the surface of a metal lead frame. In accordance with one embodiment, electroplating is used to fabricate non-integral pin portions shaped to remain securely encapsulated within the plastic molding of the package. In accordance with another embodiment, electroplating may be used to fabricate protrusions on the underside of the lead frame for elevating the package above the PC board, thereby preserving the rounded shape of solder balls used to secure the diepad to the PC board. In accordance with yet another embodiment, electroplating may be used to fabricate raised patterns on the upper surface of the diepad for ensuring uniform spreading of adhesive used to secure the die to the diepad, thereby ensuring level attitude of the die within the package. | 01-06-2011 |
| 20110037120 | Shielded gate trench MOSFET device and fabrication - A semiconductor device embodiment includes a substrate, an active gate trench in the substrate, and an asymmetric trench in the substrate. The asymmetric trench has a first trench wall and a second trench wall, the first trench wall is lined with oxide having a first thickness, and the second trench wall is lined with oxide having a second thickness that is different from the first thickness. Another semiconductor device embodiment includes a substrate, an active gate trench in the substrate; and a source polysilicon pickup trench in the substrate. The source polysilicon pickup trench includes a polysilicon electrode, and top surface of the polysilicon electrode is below a bottom of a body region. Another semiconductor device includes a substrate, an active gate trench in the substrate, the active gate trench has a first top gate electrode and a first bottom source electrode, and a gate runner trench comprising a second top gate electrode and a second bottom source electrode. The second top gate electrode is narrower than the second bottom source electrode. | 02-17-2011 |
| 20110039383 | Shielded gate trench MOSFET device and fabrication - A method for fabricating a semiconductor device includes forming a plurality of trenches, including applying a first mask, forming a first polysilicon region in at least some of the plurality of trenches, forming a inter-polysilicon dielectric region and a termination protection region, including applying a second mask, forming a second polysilicon region in the at least some of the plurality of trenches, forming a first electrical contact to the first polysilicon region and forming a second electrical contact to the second polysilicon region, including applying a third mask, disposing a metal layer, and forming a source metal region and a gate metal region, including applying a fourth mask. | 02-17-2011 |
| 20110059593 | Method of Integrating a MOSFET with a Capacitor - A bypass capacitor is directly integrated on top of a MOSFET chip. The capacitor comprises multi layers of conductive material and dielectric material staking on top of each other with connection vias through dielectric layer for connecting different conductive layers. The method of integrating the bypass capacitor comprises repeating steps of depositing a dielectric layer, forming connection vias through the dielectric layer, depositing a conductive layer and patterning the conductive layer. | 03-10-2011 |
| 20110062506 | Metal Oxide Semiconductor Field Effect Transistor Integrating a Capacitor - A bypass capacitor is directly integrated on top of a MOSFET chip. The capacitor comprises multi layers of conductive material and dielectric material staking on top of each other with connection vias through dielectric layer for connecting different conductive layers. The method of integrating the bypass capacitor comprises repeating steps of depositing a dielectric layer, forming connection vias through the dielectric layer, depositing a conductive layer and patterning the conductive layer. | 03-17-2011 |
| 20110068386 | DIRECT CONTACT IN TRENCH WITH THREE-MASK SHIELD GATE PROCESS - A semiconductor device and a method for making a semiconductor device are disclosed. A trench mask may be applied to a semiconductor substrate, which is etched to form trenches with three different widths. A first conductive material is formed at the bottom of the trenches. A second conductive material is formed over the first conductive material. An insulator layer separates the first and second conductive materials. A first insulator layer is deposited on top of the trenches. A body layer is formed in a top portion of the substrate. A source is formed in the body layer. A second insulator layer is applied on top of the trenches and the source. A contact mask is applied on top of the second insulator layer. Source and gate contacts are formed through the second insulator layer. Source and gate metal are formed on top of the second insulator layer. | 03-24-2011 |
| 20110089488 | Power Device with Improved Edge Termination - A field effect transistor includes an active region and a termination region surrounding the active region. A resistive element is coupled to the termination region, wherein upon occurrence of avalanche breakdown in the termination region an avalanche current starts to flow in the termination region, and the resistive element is configured to induce a portion of the avalanche current to flow through the termination region and a remaining portion of the avalanche current to flow through the active region. | 04-21-2011 |
| 20110089492 | High voltage semiconductor device with JFET regions containing dielectrically isolated junctions and method of fabricating the same - A high-voltage field-effect device contains an extended drain or “drift” region including an embedded stack of JFET regions separated by intervening layers of the drift region. Each of the JFET regions is filled with material of an opposite conductivity type to that of the drift region, and the floor and ceiling of each JFET region is lined with an oxide layer. When the device is blocking a voltage in the off condition, the semiconductor material inside the JFET regions and in the drift region that separates the JFET regions is depleted. This improves the voltage-blocking ability of the device while conserving chip area. The oxide layer prevents dopant from the JFET regions from diffusing into the drift region. | 04-21-2011 |
| 20110097894 | Method of Forming a Topside Contact to a Backside Terminal of a Semiconductor Device - A process for forming a vertically conducting semiconductor device includes providing a semiconductor substrate having a topside surface and a backside surface. The semiconductor substrate serves as a terminal of the vertically conducting device for biasing the vertically conducting device during operation. The process also includes forming an epitaxial layer extending over the topside surface of the semiconductor substrate but terminating prior to reaching an edge of the semiconductor substrate so as to form a recessed region along a periphery of the semiconductor substrate. The method also includes forming an interconnect layer extending into the recessed region but terminating prior to reaching an edge of the semiconductor substrate. The interconnect layer electrically contacts the topside surface of the semiconductor substrate in the recessed region to thereby provide a topside contact to the semiconductor substrate. | 04-28-2011 |
| 20110101446 | STAGGERED COLUMN SUPERJUNCTION - A staggered column superjunction semiconductor device may include a cell region having one or more device cells. One or more device cells in the cell region include a semiconductor substrate configured to act as a drain and a semiconductor layer formed on the substrate. A first doped column may be formed in the semiconductor layer to a first depth and a second doped column may be formed in the semiconductor layer to a second depth. The first depth is greater than the second depth. The first and second columns are doped with dopants of a same second conductivity type and extend along a portion of a thickness of the semiconductor layer and are separated from each by a portion of the semiconductor layer. | 05-05-2011 |
| 20110127586 | Lateral super junction device with high substrate-gate breakdown and built-in avalanche clamp diode - A lateral super junction JFET is formed from stacked alternating P type and N type semiconductor layers over a P-epi layer supported on an N+ substrate. An N+ drain column extends down through the super junction structure and the P-epi to connect to the N+ substrate to make the device a bottom drain device. N+ source column and P+ gate column extend through the super junction but stop at the P-epi layer. A gate-drain avalanche clamp diode is formed from the bottom the P+ gate column through the P-epi to the N+ drain substrate. | 06-02-2011 |
| 20110127606 | Lateral super junction device with high substrate-drain breakdwon and built-in avalanche clamp diode - This invention discloses configurations and methods to manufacture lateral power device including a super junction structure with an avalanche clamp diode formed between the drain and the gate. The lateral super-junction structure reduces on-resistance, while the structural enhancements, including an avalanche clamping diode and an N buffer region, increase the breakdown voltage between substrate and drain and improve unclamped inductive switching (UIS) performance. | 06-02-2011 |
| 20110140167 | Nanotube Semiconductor Devices - A method for forming a semiconductor device includes forming a nanotube region using a thin epitaxial layer formed on the sidewall of a trench in the semiconductor body. The thin epitaxial layer has uniform doping concentration. In another embodiment, a first thin epitaxial layer of the same conductivity type as the semiconductor body is formed on the sidewall of a trench in the semiconductor body and a second thin epitaxial layer of the opposite conductivity type is formed on the first epitaxial layer. The first and second epitaxial layers have uniform doping concentration. The thickness and doping concentrations of the first and second epitaxial layers and the semiconductor body are selected to achieve charge balance. In one embodiment, the semiconductor body is a lightly doped P-type substrate. A vertical trench MOSFET, an IGBT, a Schottky diode and a P-N junction diode can be formed using the same N-Epi/P-Epi nanotube structure. | 06-16-2011 |
| 20110147830 | METHOD OF FORMING A SELF-ALIGNED CHARGE BALANCED POWER DMOS - Self-aligned charge balanced semiconductor devices and methods for forming such devices are disclosed. One or more planar gates are formed over a semiconductor substrate of a first conductivity type. One or more deep trenches are etched in the semiconductor self-aligned to the planar gates. The trenches are filled with a semiconductor material of a second conductivity type such that the deep trenches are charge balanced with the adjacent regions of the semiconductor substrate This process can form self-aligned charge balanced devices with a cell pitch less than 12 microns. | 06-23-2011 |