Active solid-state devices (e.g. – transistors – solid-state diode – Test or calibration structure
Reexamination Certificate
1999-06-10
2001-06-12
Crane, Sara (Department: 2811)
Active solid-state devices (e.g., transistors, solid-state diode
Test or calibration structure
C257S106000, C257S603000, C257S758000
Reexamination Certificate
active
06246073
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a semiconductor device having multilayer interconnections, and to a production method therefor.
2. Description of the Related Art
FIGS. 7 and 8A
show a semiconductor
100
having conventional multilayer interconnections.
The semiconductor device
100
includes a substrate
1
, an epitaxial layer
2
, an interconnection
3
of a first layer, an interconnection
4
of a second layer and a pad
6
. The pad
6
is provided on the interconnection
4
of the second layer. The interconnection
4
of the second layer is used for shading light because it is necessary to prevent a photodetector incorporated into a circuit from being irradiated with light in order to avoid a circuital malfunction caused by irradiating the circuit. In other words, the interconnection
4
of the second layer is used as a shading layer or a light shield.
In the semiconductor device
100
, the interconnection
4
of the second layer is connected to a portion having a low-impedance potential, such as a ground (hereinafter, referred to as GND), a positive power source, a negative power source or the like. As shown in
FIG. 8B
, the interconnection
4
of the second layer is connected to GND, the positive power source or the negative power source.
If a portion of interlayer insulation failure
50
occurred by disorder of production process, generation of a pin hole or the like during a production process of the semiconductor device
100
, a defective interlayer insulation occurs between the interconnection
3
of a first layer and the interconnection
4
of a second layer. Furthermore, when the interconnection
4
of the second layer is used as a shading layer or a light shield, the interconnection
4
of the second layer is formed such that an area thereof is greater, thereby increasing the probability that an incomplete interlayer insulation will result.
As shown in
FIG. 9
, examples of a defective interlayer insulation include a short-circuit between the interconnection
3
of a first layer and the interconnection
4
of a second layer and an insufficient interlayer insulation in which an initial voltage resistance of the interlayer insulation is less than Vx. Even in a case where the interconnection
3
of a first layer and the interconnection
4
of a second layer are not short-circuited, a low voltage resistance of the interlayer insulation will result in a high probability that the semiconductor device will become defective after a certain time period.
When the interconnection
3
of a first layer and the interconnection
4
of a second layer are short-circuited, it is easy to detect the short-circuited semiconductor device. However, it has been difficult to detect a semiconductor device in which the interlayer insulation is insufficient.
In view of the above problem, an object of the present invention is to detect and eliminate a semiconductor device in which the interlayer insulation is insufficient.
SUMMARY OF THE INVENTION
The present invention provides a semiconductor device having multilayer interconnections including a first interconnection and a second interconnection, wherein: the second interconnection is formed to be connected to one of a ground, a positive power source and a negative power source; the second interconnection is formed either not to be electrically connected to the first interconnection or to be connected to the first interconnection in a high impedance state; and the first interconnection and the second interconnection are electrically connected to each other during or after a characteristic inspection during which the second interconnection is provided with a pad for inspecting characteristics of the semiconductor device.
In one embodiment, an element for electrically connecting the first interconnection and the second interconnection is made of Au.
In another embodiment, an element for electrically connecting the first interconnection and the second interconnection is a broken and short-circuited zener diode.
In still another embodiment, an element for electrically connecting the first interconnection and the second interconnection is a zener diode to which a pulse voltage over a breakdown voltage is applied.
The present invention provides a method for inspecting characteristics of a semiconductor device, wherein the semiconductor device of claim
3
is inspected by a characteristic inspection other than the characteristic inspection of claim
1
.
The present invention provides a method for inspecting characteristics of a semiconductor device, wherein the semiconductor device of claim
4
is inspected by a characteristic inspection other than the characteristic inspection of claim
1
.
The present invention provides a method for producing a semiconductor device having multilayer interconnections including a first interconnection and a second interconnection, including the steps of: forming the first interconnection to be connected to one of a ground, a positive power source and a negative power source; forming the second interconnection not to be electrically connected to the first interconnection or but to be connected to the first interconnection in a high impedance state; providing the second interconnection with a pad for inspecting characteristics of the semiconductor device; inspecting characteristics of the semiconductor device; and electrically connecting the first interconnection and the second interconnection to each other during or after the step of inspecting characteristics.
In one embodiment, in the step of electrically connecting the first interconnection and the second interconnection to each other, the first interconnection and the second interconnection is electrically connected with Au.
In another embodiment, a method for producing a semiconductor device further includes a step of connecting the first interconnection and the second interconnection through a zener diode, wherein in the step of electrically connecting the first interconnection and the second interconnection to each other, the first interconnection and the second interconnection are electrically connected by breaking the zener diode so as to be short circuited.
In still another embodiment, in the step of electrically connecting the first interconnection and the second interconnection to each other, a pulse voltage over a breakdown voltage of the zener diode is applied to the zener diode in order to break the zener diode so as to be short-circuited.
Hereinafter, the function of the present invention will be described.
A semiconductor device is provided with a first interconnection of one layer and a second interconnection of another layer. The first interconnection is connected to a portion having a low impedance potential, such as GND, a positive power source or a negative power source. The second interconnection has a relatively large area for shading light. In other words, the second interconnection functions as a shading surface (a shield surface) covering a plurality of the first interconnections.
The second interconnection is not electrically connected to the first interconnection or is connected to the first interconnection in a high impedance state so that it is relatively easy to detect a semiconductor device in which the interlayer insulation is defective between the first interconnection and the second interconnection.
After it is determined whether a semiconductor device is excellent or defective, the excellent semiconductor device is electrically connected between the first interconnection and the second interconnection.
Thus, the invention described herein makes possible the advantages of (1) providing a method for electrically connecting a first interconnection of one layer to a second interconnection of another layer during or after a step of inspecting characteristics of a semiconductor device, and (2) detecting and eliminating a semiconductor device in which the interlayer insulation is insufficient from the manufactured products.
These and other advantages of the present invention will
Crane Sara
Nixon & Vanderhye P.C.
Sharp Kabushiki Kaisha
LandOfFree
Semiconductor device and method for producing the same does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Semiconductor device and method for producing the same, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Semiconductor device and method for producing the same will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2503556