Patent application number | Description | Published |
20100190307 | HIGH DENSITY TRENCH MOSFET WITH SINGLE MASK PRE-DEFINED GATE AND CONTACT TRENCHES - Trench gate MOSFET devices may be formed using a single mask to define gate trenches and body contact trenches. A hard mask is formed on a surface of a semiconductor substrate. A trench mask is applied on the hard mask to predefine a body contact trench and a gate trench. These predefined trenches are simultaneously etched into the substrate to a first predetermined depth. A gate trench mask is next applied on top of the hard mask. The gate trench mask covers the body contact trenches and has openings at the gate trenches that are wider than those trenches. The gate trench, but not the body contact trench, is etched to a second predetermined depth. Conductive material of a first kind may fill the gate trench to form a gate. Conductive material of a second kind may fill the body contact trench to form a body contact. | 07-29-2010 |
20100291744 | HIGH DENSITY TRENCH MOSFET WITH SINGLE MASK PRE-DEFINED GATE AND CONTACT TRENCHES - Trench gate MOSFET devices may be formed using a single mask to define gate trenches and body contact trenches. A hard mask is formed on a surface of a semiconductor substrate. A trench mask is applied on the hard mask to predefine a body contact trench and a gate trench. These predefined trenches are simultaneously etched into the substrate to a first predetermined depth. A gate trench mask is next applied on top of the hard mask. The gate trench mask covers the body contact trenches and has openings at the gate trenches. The gate trench, but not the body contact trench, is etched to a second predetermined depth. Conductive material of a first kind may fill the gate trench to form a gate. Conductive material of a second kind may fill the body contact trench to form a body contact. | 11-18-2010 |
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 |
20110049618 | FABRICATION OF TRENCH DMOS DEVICE HAVING THICK BOTTOM SHIELDING OXIDE - Semiconductor device fabrication method and devices are disclosed. A device may be fabricated by forming in a semiconductor layer; filling the trench with an insulating material; removing selected portions of the insulating material leaving a portion of the insulating material in a bottom portion of the trench; forming one or more spacers on one or more sidewalls of a remaining portion of the trench; anisotropically etching the insulating material in the bottom portion of the trench using the spacers as a mask to form a trench in the insulator; removing the spacers; and filling the trench in the insulator with a conductive material. Alternatively, an oxide-nitride-oxide (ONO) structure may be formed on a sidewall and at a bottom of the trench and one or more conductive structures may be formed in a portion of the trench not occupied by the ONO structure. | 03-03-2011 |
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 |
20110140228 | Method of Filling Large Deep Trench with High Quality Oxide for Semiconductor Devices - A method is disclosed for creating a semiconductor device structure with an oxide-filled large deep trench (OFLDT) portion having trench size TCS and trench depth TCD. A bulk semiconductor layer (BSL) is provided with a thickness BSLT>TCD. A large trench top area (LTTA) is mapped out atop BSL with its geometry equal to OFLDT. The LTTA is partitioned into interspersed, complementary interim areas ITA-A and ITA-B. Numerous interim vertical trenches of depth TCD are created into the top BSL surface by removing bulk semiconductor materials corresponding to ITA-B. The remaining bulk semiconductor materials corresponding to ITA-A are converted into oxide. If any residual space is still left between the so-converted ITA-A, the residual space is filled up with oxide deposition. Importantly, the geometry of all ITA-A and ITA-B should be configured simple and small enough to facilitate fast and efficient processes of oxide conversion and oxide filling. | 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 |
20110316076 | Power MOSFET Device with Self-Aligned Integrated Schottky and its Manufacturing Method - A power MOSFET device and manufacturing method thereof, includes the steps of selectively depositing a first conductive material in the middle region at the bottom of a contact trench and contacting with light-doped N-type epitaxial layer to form a Schottky junction and depositing a second conductive material at the side wall and bottom corner of the contact trench and contacting with P-type heavy-doped body region to form an ohmic junction. The first and second conductive materials can respectively optimize the performance of the ohmic contact and the Schottky contact without compromise. Meanwhile, the corner of the contact trench is surrounded by P-type heavy-doped region thereby effectively reducing the leakage currents accumulated at the corner of the contact trench. | 12-29-2011 |
20120292692 | Power MOSFET Device with Self-Aligned Integrated Schottky Diode - A power MOSFET device and manufacturing method thereof, includes the steps of selectively depositing a first conductive material in the middle region at the bottom of a contact trench and contacting with light-doped N-type epitaxial layer to form a Schottky junction and depositing a second conductive material at the side wall and bottom corner of the contact trench and contacting with P-type heavy-doped body region to form an ohmic junction. The first and second conductive materials can respectively optimize the performance of the ohmic contact and the Schottky contact without compromise. Meanwhile, the corner of the contact trench is surrounded by P-type heavy-doped region thereby effectively reducing the leakage currents accumulated at the corner of the contact trench. | 11-22-2012 |
20120292693 | FABRICATION OF TRENCH DMOS DEVICE HAVING THICK BOTTOM SHIELDING OXIDE - Semiconductor device fabrication method and devices are disclosed. A device may be fabricated by forming in a semiconductor layer; filling the trench with an insulating material; removing selected portions of the insulating material leaving a portion of the insulating material in a bottom portion of the trench; forming one or more spacers on one or more sidewalls of a remaining portion of the trench; anisotropically etching the insulating material in the bottom portion of the trench using the spacers as a mask to form a trench in the insulator; removing the spacers; and filling the trench in the insulator with a conductive material. Alternatively, an oxide-nitride-oxide (ONO) structure may be formed on a sidewall and at a bottom of the trench and one or more conductive structures may be formed in a portion of the trench not occupied by the ONO structure. | 11-22-2012 |
20130075855 | Manufacturing methods for accurately aligned and self-balanced superjunction devices - A method for manufacturing a semiconductor power device on a semiconductor substrate supporting a drift region composed of an epitaxial layer by growing a first epitaxial layer followed by forming a first hard mask layer on top of the epitaxial layer; applying a first implant mask to open a plurality of implant windows and applying a second implant mask for blocking some of the implant windows to implant a plurality of dopant regions of alternating conductivity types adjacent to each other in the first epitaxial layer; repeating the first step and the second step by applying the same first and second implant masks to form a plurality of epitaxial layers then carrying out a device manufacturing process on a top side of the epitaxial layer with a diffusion process to merge the dopant regions of the alternating conductivity types as doped columns in the epitaxial layers. | 03-28-2013 |
20130200451 | NANO MOSFET WITH TRENCH BOTTOM OXIDE SHIELDED AND THIRD DIMENSIONAL P-BODY CONTACT - A semiconductor power device may include a lightly doped layer formed on a heavily doped layer. One or more devices are formed in the lightly doped layer. Each device may include a body region, a source region, and one or more gate electrodes formed in corresponding trenches in the lightly doped region. Each of the trenches has a depth in a first dimension, a width in a second dimension and a length in a third dimension. The body region is of opposite conductivity type to the lightly and heavily doped layers. The source region is formed proximate the upper surface. One or more deep contacts are formed at one or more locations along the third dimension proximate one or more of the trenches. The contacts extend in the first direction from the upper surface into the lightly doped layer and are in electrical contact with the source region. | 08-08-2013 |
20130228857 | METHOD OF FORMING AN ASSYMETRIC POLY GATE FOR OPTIMUM TERMINATION DESIGN IN TRENCH POWER MOSFETS - A semiconductor device having a plurality of transistors includes a termination area that features a transistor with an asymmetric gate. | 09-05-2013 |
20130341689 | 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 Source and body regions are formed by implanting dopants onto the filled trenches. This process can form self-aligned charge balanced devices with a cell pitch less than 12 microns. | 12-26-2013 |
20140175536 | HIGH DENSITY TRENCH-BASED POWER MOSFETS WITH SELF-ALIGNED ACTIVE CONTACTS AND METHOD FOR MAKING SUCH DEVICES - Aspects of the present disclosure describe a high density trench-based power MOSFET with self-aligned source contacts. The source contacts are self-aligned with a first insulative spacer and a second insulative spacer, wherein the first spacer is resistant to an etching process that will selectively remove the material the second spacer is made from. Additionally, the active devices may have a two-step gate oxide, wherein a lower portion of the gate oxide has a thickness T | 06-26-2014 |
20140239388 | TERMINATION TRENCH FOR POWER MOSFET APPLICATIONS - Aspects of the present disclosure describe a termination structure for a power MOSFET device. A termination trench may be formed into a semiconductor material and may encircle an active area of the MOSFET. The termination trench may comprise a first and second portion of conductive material. The first and second portions of conductive material are electrically isolated from each other. It is emphasized that this abstract is provided to comply with rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. | 08-28-2014 |
20140252460 | High Density MOSFET Array with Self-Aligned Contacts Delimited by Nitride-Capped Trench Gate Stacks and Method - A high density trench-gated MOSFET array and method are disclosed. It comprises semiconductor substrate partitioned into MOSFET array area and gate pickup area; epitaxial region, body region and source region; numerous precisely spaced active nitride-capped trench gate stacks (ANCTGS) embedded till the epitaxial region. Each ANCTGS comprises a stack of polysilicon trench gate with gate oxide shell and silicon nitride cap covering top of polysilicon trench gate and laterally registered to gate oxide shell. The ANCTGS forms, together with the source, body, epitaxial region, a MOSFET device in the MOSFET array area. Over MOSFET array area and gate pickup area, a patterned dielectric region atop the MOSFET array and a patterned metal layer atop the patterned dielectric region. Thus, the patterned metal layer forms, with the MOSFET array and the gate pickup area, self-aligned source and body contacts through the inter-ANCTGS separations. | 09-11-2014 |
20140319605 | NANO MOSFET WITH TRENCH BOTTOM OXIDE SHIELDED AND THIRD DIMENSIONAL P-BODY CONTACT - A semiconductor power device may include a lightly doped layer formed on a heavily doped layer. One or more devices are formed in the lightly doped layer. Each device may include a body region, a source region, and one or more gate electrodes formed in corresponding trenches in the lightly doped region. Each of the trenches has a depth in a first dimension, a width in a second dimension and a length in a third dimension. The body region is of opposite conductivity type to the lightly and heavily doped layers. The source region is formed proximate the upper surface. One or more deep contacts are formed at one or more locations along the third dimension proximate one or more of the trenches. The contacts extend in the first direction from the upper surface into the lightly doped layer and are in electrical contact with the source region. | 10-30-2014 |
20140339630 | DEVICE STRUCTURE AND METHODS OF MAKING HIGH DENSITY MOSFETS FOR LOAD SWITCH AND DC-DC APPLICATIONS - Aspects of the present disclosure describe a high density trench-based power MOSFETs with self-aligned source contacts and methods for making such devices. The source contacts are self-aligned with spacers that are formed along the sidewall of the gate caps. Additionally, the active devices may have a two-step gate oxide. A lower portion may have a thickness that is larger than the thickness of an upper portion of the gate oxide. The two-step gate oxide combined with the self-aligned source contacts allow for the production of devices with a pitch in the deep sub-micron level. It is emphasized that this abstract is provided to comply with rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. | 11-20-2014 |
20140374824 | MOSFET WITH INTEGRATED SCHOTTKY DIODE - Aspects of the present disclosure describe a Schottky structure with two trenches formed in a semiconductor material. The trenches are spaced apart from each other by a mesa. Each trench may have first and second conductive portions lining the first and second sidewalls. The first and second portions of conductive material are electrically isolated from each other in each trench. The Schottky contact may be formed at any location between the outermost conductive portions. The Schottky structure may be formed in the active area or the termination area of a device die. It is emphasized that this abstract is provided to comply with rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. | 12-25-2014 |