CN-224234068-U - Schottky diode and buck converter comprising the same

CN224234068UCN 224234068 UCN224234068 UCN 224234068UCN-224234068-U

Abstract

Various embodiments of the present utility model relate to a schottky diode that includes an n-type region, an anode over the n-type region, a buried p-type region, and a shallow p-type region, and a buck converter including the same. The interface between the anode and the n-type region forms a schottky barrier. The n-type channel portion of the n-type region is located between the buried p-type region and the shallow p-type region. The anode may also contact the annular shallow p-type region. In a halo structure, the buried p-type region and the shallow p-type region are halo regions, and the n-type region includes a central portion surrounded by the halo shallow p-type region and a halo peripheral portion of the n-type region surrounding the halo shallow p-type region. In one application, the buck converter includes the schottky diode.

Inventors

WU HONGXIANG
WU GUOMING

Assignees

台湾积体电路制造股份有限公司

Dates

Publication Date: 20260512
Application Date: 20250122
Priority Date: 20240202

Claims (10)

1. A schottky diode which has the characteristics of high-k, characterized by comprising the following steps: An n-type region; An anode of the schottky diode located on the n-type region, an interface between the anode and the n-type region including a schottky barrier; Buried p-type region, and A shallow p-type region is provided, Wherein an n-type channel portion of the n-type region is located between the buried p-type region and the shallow p-type region.
2. The schottky diode of claim 1 wherein said anode further contacts said shallow p-type region.
3. The schottky diode of claim 1, characterized by further comprising: the cathode of the Schottky diode is electrically contacted with the n-type region, Wherein the n-type channel portion of the n-type region is configured to conduct current between the anode and the cathode when the schottky diode is forward biased and pinch off current between the anode and the cathode when the schottky diode is reverse biased.
4. The schottky diode of claim 1 wherein: the buried p-type region is a ring-shaped buried p-type region disposed in a lower portion of the n-type region; The shallow p-type region is a ring-shaped shallow p-type region arranged in the upper part of the n-type region, and The n-type channel portion of the n-type region connects a central portion of the n-type region with an annular peripheral portion of the n-type region, wherein the central portion is surrounded by the annular shallow p-type region and the annular peripheral portion surrounds the annular shallow p-type region.
5. The schottky diode of claim 4, characterized by further comprising: the cathode of the schottky diode is in electrical contact with the annular peripheral portion of the n-type region.
6. The schottky diode of claim 4, characterized by further comprising: An n-type buried layer under the n-type region and under the annular buried p-type region, the n-type region being in contact with the n-type buried layer, and An annular p-type region surrounding and in contact with the annular buried p-type region.
7. A buck converter, comprising: An LC circuit comprising a sensor, a capacitor, a transistor, and at least one diode connected across a channel of the transistor, Wherein the at least one diode comprises a schottky diode comprising an n-type region, an anode of the schottky diode disposed on the n-type region, a buried p-type region, and a shallow p-type region, wherein an interface between the anode and the n-type region comprises a schottky barrier, wherein an n-type channel portion of the n-type region is located between the buried p-type region and the shallow p-type region.
8. The buck converter according to claim 7, wherein: The buried p-type region of the schottky diode is a ring-shaped buried p-type region disposed in a lower portion of the n-type region; The shallow p-type region of the schottky diode is a ring-shaped shallow p-type region provided in an upper portion of the n-type region; the n-type channel portion of the n-type region of the Schottky diode is located between the annular buried p-type region and the annular shallow p-type region, and The schottky diode further includes a cathode of the schottky diode in electrical contact with the annular peripheral portion of the n-type region.
9. The buck converter according to claim 8, further comprising: An n-type buried layer under the n-type region and under the annular buried p-type region, the n-type region being in contact with the n-type buried layer, and An annular p-type region surrounding and in contact with the annular buried p-type region.
10. The buck converter according to claim 8, wherein the at least one diode connected across the channel of the transistor further includes a p/n junction diode connected in parallel with the schottky diode.

Description

Schottky diode and buck converter comprising the same Technical Field Embodiments of the present utility model relate to a schottky diode and a buck converter including the same. Background The following relates to schottky diodes and Integrated Circuit (IC) devices employing schottky diodes, such as buck converters and other types of DC-DC power converters. Disclosure of utility model One aspect of the present utility model provides a method of fabricating a schottky diode. The method includes forming an n-type region in a p-type substrate by ion implantation. The method further includes forming a halo buried p-type region in the n-type region by ion implantation. The method further includes forming an annular shallow p-type region in the n-type region at a shallower depth than the annular buried p-type region by ion implantation, wherein an annular n-type channel portion of the n-type region is located between the annular buried p-type region and the annular shallow p-type region. The method further includes forming an anode of the schottky diode on a central portion of the n-type region, wherein an interface between the anode and the central portion of the n-type region includes a schottky barrier. Another aspect of the present utility model provides a schottky diode. The schottky diode includes an n-type region. The schottky diode further includes an anode of the schottky diode located on the n-type region, and an interface between the anode and the n-type region includes a schottky barrier. The schottky diode also includes a buried p-type region and a shallow p-type region. The n-type channel portion of the n-type region is located between the buried p-type region and the shallow p-type region. Yet another aspect of the present utility model provides a buck converter. The buck converter includes an LC circuit including a sensor, a capacitor, a transistor, and at least one diode connected across a channel of the transistor. At least one diode includes a schottky diode including an n-type region, an anode of the schottky diode disposed on the n-type region, a buried p-type region, and a shallow p-type region, wherein an interface between the anode and the n-type region includes a schottky barrier. The n-type channel portion of the n-type region is located between the buried p-type region and the shallow p-type region. In order to make the above features and advantages of the present utility model more comprehensible, embodiments accompanied with figures are described in detail below. Drawings Fig. 1 schematically illustrates a side cross-sectional view of a schottky barrier diode. Fig. 2 and 3 schematically illustrate a side cross-sectional view (fig. 2) and a top view (fig. 3) of the schottky barrier diode, wherein the side cross-sectional view of fig. 2 is taken along a segment line S-S shown in fig. 3. Fig. 4 schematically illustrates a side cross-sectional view of the schottky barrier diode of fig. 2 and 3 under a forward bias. Fig. 5 schematically illustrates a side cross-sectional view of the schottky barrier diode of fig. 2 and 3 under reverse bias. Fig. 6 schematically shows a simulation of the total forward bias current amount (forward bias total current magnitude) of the schottky barrier diode of fig. 2 and 3. Fig. 7 schematically illustrates a simulation of reverse bias impact ionization (reverse bias impact ionization) of the schottky barrier diode of fig. 2 and 3. Fig. 8 shows a circuit schematic of a buck converter employing a schottky diode as described herein. Detailed Description This summary provides many different embodiments or examples for implementing different features of this summary. Specific examples of components and arrangements are set forth below to simplify the present disclosure. Of course, these are merely examples and are not intended to be limiting. For example, forming a first feature over or on a second feature in the description that follows may include embodiments in which the first and second features are formed in direct contact, and may also include embodiments in which additional features may be formed between the first and second features, such that the first and second features may not be in direct contact. In addition, the present disclosure may repeat reference numerals and/or letters in the various examples. Such reuse is for brevity and clarity purposes and does not itself indicate a relationship between the various embodiments and/or configurations discussed. Further, for ease of description, spatially relative terms such as "below," "lower," "upper," and the like may be used herein to describe one component or feature's relationship to another component or feature as illustrated in the figures. In addition to the orientations depicted in the drawings, the spatially relative terms are intended to encompass different orientations of the device in use or operation. The device may have other orientations (rotated 90 degrees or at other orientations), and the