Abstract:
Various embodiments include structures for field effect transistors (FETs). In various embodiments, a structure for a FET includes: a deep n-type well; a shallow n-type well within the deep n-type well; and a shallow trench isolation (STI) region within the shallow n-type well, the STI region including: a first section having a first depth within the shallow n-type well as measured from an upper surface of the shallow n-type well, and a second section contacting and overlying the first section, the second section having a second depth within the shallow n-type well as measured from the upper surface of the shallow n-type well.
Abstract:
A method of forming a semiconductor structure in a semiconductor-on-insulator (SOI) substrate and semiconductor structure so formed are provided. The SOI substrate includes a semiconductor layer; a bulk semiconductor region underlying the semiconductor layer; and an insulation layer between the two. The method includes substantially simultaneously forming a first opening and a second opening extending from the semiconductor layer to the conductive region; introducing an insulating material to the side walls of the first opening; at least partially filling the first opening with a semiconductor material to provide an ohmic contact trench; and at least partially filling the second opening with an insulating material to form a device isolation trench. Insulating regions, for example, shallow trench isolation (STI) regions, may be formed about the device isolation trench and the ohmic contact trench. Semiconductor structures are also provided. The benefits of combining the features of SOI and STI structures are provided.
Abstract:
A method of forming a semiconductor structure in a semiconductor-on-insulator (SOI) substrate and semiconductor structure so formed are provided. The SOI substrate includes a semiconductor layer; a bulk semiconductor region underlying the semiconductor layer; and an insulation layer between the two. The structure includes first and second openings each having sidewalls, each of the first opening and the second opening formed substantially simultaneously and extending from a top surface of the semiconductor layer through the semiconductor layer and through the insulation layer to the conductive region; an insulating material adapted to provide electrical insulation to at least a portion of the side walls of the first opening; a semiconductor material at least partially filling the first opening, the semiconductor material defining an ohmic contact trench providing electrical contact with the semiconductor region; and an insulating material disposed in the second opening and defining a device isolation trench.
Abstract:
A method of forming a semiconductor structure in a semiconductor-on-insulator (SOI) substrate and semiconductor structure so formed are provided. The SOI substrate includes a semiconductor layer; a bulk semiconductor region underlying the semiconductor layer; and an insulation layer between the two. The structure includes first and second openings each having sidewalls, each of the first opening and the second opening formed substantially simultaneously and extending from a top surface of the semiconductor layer through the semiconductor layer and through the insulation layer to the conductive region; an insulating material adapted to provide electrical insulation to at least a portion of the side walls of the first opening; a semiconductor material at least partially filling the first opening, the semiconductor material defining an ohmic contact trench providing electrical contact with the semiconductor region; and an insulating material disposed in the second opening and defining a device isolation trench.
Abstract:
Disclosed are methods that employ a mask with openings arranged in a pattern of elongated trenches and holes of varying widths to achieve a linearly graded conductivity level. These methods can be used to form a lateral double-diffused metal oxide semiconductor field effect transistor (LDMOSFET) with a drain drift region having an appropriate type conductivity at a level that increases essentially linearly from the body region to the drain region. Furthermore, these methods also provide for improve manufacturability in that multiple instances of this same pattern can be used during a single dopant implant process to implant a first dopant with a first type (e.g., N-type) conductivity into the drain drift regions of both first and second type LDMOSFETs (e.g., N and P-type LDMOSFETs, respectively). In this case, the drain drift region of a second type LDMOSFET can subsequently be uniformly counter-doped. Also disclosed are the resulting semiconductor structures.
Abstract:
Disclosed are methods that employ a mask with openings arranged in a pattern of elongated trenches and holes of varying widths to achieve a linearly graded conductivity level. These methods can be used to form a lateral double-diffused metal oxide semiconductor field effect transistor (LDMOSFET) with a drain drift region having an appropriate type conductivity at a level that increases essentially linearly from the body region to the drain region. Furthermore, these methods also provide for improve manufacturability in that multiple instances of this same pattern can be used during a single dopant implant process to implant a first dopant with a first type (e.g., N-type) conductivity into the drain drift regions of both first and second type LDMOSFETs (e.g., N and P-type LDMOSFETs, respectively). In this case, the drain drift region of a second type LDMOSFET can subsequently be uniformly counter-doped. Also disclosed are the resulting semiconductor structures.