Patent Application
20180102315
The present invention generally relates to surface area-dependent semiconductor devices. More particularly, the present invention relates to increasing the surface area of surface area-dependent semiconductor devices.
As the size of semiconductor devices continues to shrink, maximizing a surface area-dependent device characteristic becomes more and more challenging, particularly with concurrent demand for reduced fabrication costs and increased capacitance density per unit footprint. Thus, the design of such semiconductor devices must increase the surface area, ideally, without increasing a footprint of the device. For example, metal-insulator-metal capacitors (MIMCAPs) used for interconnect structures depend on surface area to maximize capacitance. Solutions for MIMCAPs suffer limited capacitance density, reliability concerns and/or complicate the device design. In addition to continued down-scaling, the industry faces a demand for reduced fabrication costs and increased capacitance density per unit footprint.
Thus, a need continues to exist for increasing the area of an area-dependent semiconductor device while minimizing or avoiding an increased footprint.
The shortcomings of the prior art are overcome and additional advantages are provided through the provision, in one aspect, of a method of increasing the surface area of a surface area-dependent semiconductor device. The method includes providing a dielectric layer, removing at least one portion of the dielectric layer, resulting in one or more recessions, and forming at least one surface area-dependent semiconductor device, a portion of the device being formed along a sidewall of one of the one or more recessions.
In accordance with another aspect, a semiconductor structure is provided. The semiconductor structure includes a dielectric layer having one or more recessions therein, and at least one surface area-dependent semiconductor device having a portion thereof situated along a sidewall of the one or more recessions.
These, and other objects, features and advantages of this invention will become apparent from the following detailed description of the various aspects of the invention taken in conjunction with the accompanying drawings.
Aspects of the present invention and certain features, advantages, and details thereof, are explained more fully below with reference to the non-limiting examples illustrated in the accompanying drawings. Descriptions of well-known materials, fabrication tools, processing techniques, etc., are omitted so as not to unnecessarily obscure the invention in detail. It should be understood, however, that the detailed description and the specific examples, while indicating aspects of the invention, are given by way of illustration only, and are not by way of limitation. Various substitutions, modifications, additions, and/or arrangements, within the spirit and/or scope of the underlying inventive concepts will be apparent to those skilled in the art from this disclosure.
Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about,” is not limited to the precise value specified. In some instances, the approximating language may correspond to the precision of an instrument for measuring the value.
The terminology used herein is for the purpose of describing particular examples only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprise” (and any form of comprise, such as “comprises” and “comprising”), “have” (and any form of have, such as “has” and “having”), “include (and any form of include, such as “includes” and “including”), and “contain” (and any form of contain, such as “contains” and “containing”) are open-ended linking verbs. As a result, a method or device that “comprises,” “has,” “includes” or “contains” one or more steps or elements possesses those one or more steps or elements, but is not limited to possessing only those one or more steps or elements. Likewise, a step of a method or an element of a device that “comprises,” “has,” “includes” or “contains” one or more features possesses those one or more features, but is not limited to possessing only those one or more features. Furthermore, a device or structure that is configured in a certain way is configured in at least that way, but may also be configured in ways that are not listed.
As used herein, the term “connected,” when used to refer to two physical elements, means a direct connection between the two physical elements. The term “coupled,” however, can mean a direct connection or a connection through one or more intermediary elements.
As used herein, the terms “may” and “may be” indicate a possibility of an occurrence within a set of circumstances; a possession of a specified property, characteristic or function; and/or qualify another verb by expressing one or more of an ability, capability, or possibility associated with the qualified verb. Accordingly, usage of “may” and “may be” indicates that a modified term is apparently appropriate, capable, or suitable for an indicated capacity, function, or usage, while taking into account that in some circumstances the modified term may sometimes not be appropriate, capable or suitable. For example, in some circumstances, an event or capacity can be expected, while in other circumstances the event or capacity cannot occur—this distinction is captured by the terms “may” and “may be.”
As used herein, unless otherwise specified, the term “about” used with a value, such as measurement, size, etc., means a possible variation of plus or minus ten percent of the value. Also, unless otherwise specified, a given aspect of semiconductor fabrication described herein may be accomplished using conventional processes and techniques, where part of a method, and may include conventional materials appropriate for the circumstances, where a semiconductor structure is described.
Reference is made below to the drawings, which are not drawn to scale for ease of understanding, wherein the same reference numbers are used throughout different figures to designate the same or similar components.
The semiconductor structure of
As can be seen in
Theoretically, a regular hexagon shape in a honeycomb pattern would maximize the capacitance, because it enables the minimum width 110 dielectric wall to be used at all locations, and thereby maximizing the total length of vertical sidewall. However, in the current state of semiconductor fabrication, the regular hexagon shape may be difficult to achieve. For example, patterning using lithography would be challenging, though far from impossible. Theoretically, other and arbitrary shapes of recession may be used (in additional to, or instead of, circles and hexagons).
In a first aspect, disclosed above is a method. The method includes providing a dielectric layer, removing portion(s) of the dielectric layer, resulting in recessions(s), and forming surface area-dependent semiconductor device(s), a portion of each device being formed along a sidewall of one, or more, of the recessions(s).
In one example, the dielectric layer may be, for example, part of a semiconductor interconnect structure for semiconductor device(s), and the surface area-dependent semiconductor device(s) may include, for example, metal-insulator-metal (MIM) capacitor(s) having at least two plates. In one example, the at least two plates may include, for example, at least three plates.
In one example, the dielectric layer in the method of the first aspect may be, for example, part of a semiconductor interconnect structure for semiconductor device(s), and the surface area-dependent semiconductor device(s) may include environmental sensor(s).
In one example, the recession(s) in the method of the first aspect may have, for example, a regular hexagonal shape. In one example, the recessions(s) may include, for example, a regular hexagonal shape arranged in a honeycomb pattern.
In one example, the recession(s) in the method of the first aspect may have, for example, a circular shape. In one example, the recession(s) may include, for example, a circular shaped cross-section arranged in a honeycomb pattern.
In one example, the recession(s) may include, for example, recessions with a circular shaped cross-section arranged in an arbitrary pattern.
In one example, the removing in the method of the first aspect may include, for example, patterning the dielectric layer.
In a second aspect, disclosed above is a semiconductor structure. The semiconductor structure includes a dielectric layer having recession(s) therein, and surface area-dependent semiconductor device(s) having a portion thereof formed along a sidewall of the recession(s).
In one example, the dielectric layer may be, for example, part of a semiconductor interconnect structure for semiconductor device(s), and the surface area-dependent semiconductor device(s) may include, for example, metal-insulator-metal (MIM) capacitor(s) having at least two plates. In one example, the at least two plates may include, for example, at least three plates.
In one example, the dielectric layer of the semiconductor structure of the second aspect may be, for example, part of a semiconductor interconnect structure for semiconductor device(s), and the surface area-dependent semiconductor device may include environmental sensor(s).
In one example, the recession(s) of the semiconductor structure of the second aspect may have, for example, a regular hexagonal shape. In one example, the recession(s) may include, for example, multiple regular hexagonal shapes arranged in a honeycomb pattern.
In one example, the recession(s) of the semiconductor structure of the first aspect may have, for example, a circular shape. In one example, the recession(s) may include, for example, multiple circular shapes arranged in a honeycomb pattern.
In one example, the recession(s) may include, for example, recessions with a circular shaped cross-section arranged in an arbitrary pattern.
While several aspects of the present invention have been described and depicted herein, alternative aspects may be effected by those skilled in the art to accomplish the same objectives. Accordingly, it is intended by the appended claims to cover all such alternative aspects as fall within the true spirit and scope of the invention.
