JPS611038A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To readily form electrode wirings on other article from a semiconductor element by placing a thin film on the upper surface of other member form the upper surface of the element, forming electrode wirings crossing over both thereon, and then removing the film. CONSTITUTION:A semiconductor element made of mercury cadmium telluride crystal or the like and other member 3 are bonded fixedly by low melting point solder 6 on an insulating substrate 5 at an interval. Then, a thin film 7 is placed over a gap between part of the upper surface of the element 1 and part of the upper surface of the member 3. It is preferably to use negative resist having resistance force of certain degree in organic solvent for the film 7. Then, gold is deposited or plated on the pattern forming portion, and then patterned to form electrode wirings 2. Then, the film 7 is removed to obtain a semiconductor device. According to the manufacturing method, the process becomes very simple, and the integration is improved.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a method for manufacturing a semiconductor device, and in particular to a method for manufacturing an electrode wiring of a semiconductor device using a very fragile and expensive base material such as mercury cadmium telluride crystal. The present invention relates to a method for manufacturing a semiconductor device that facilitates the formation of electrode wiring from a semiconductor element to another object when the electrode wiring extends to the surface of the object.

[Prior art]

In semiconductor devices that use extremely fragile semiconductor substrates such as mercury cadmium telluride crystals, it is difficult to bond to electrode wiring on the device, so a method is used to pull out the electrode wiring to a point where bonding is possible. There is.

Conventionally, there have been devices of this type as shown in FIGS. 1 and 2. In Figure 1, (1) is a semiconductor element using a very fragile and expensive semiconductor base material such as mercury cadmium telluride crystal, and (2) is an electrode wiring.
) extends onto another member (3) such as an insulating substrate, and the semiconductor element (1) is fixed onto the other member (3) with an adhesive (4). It is.

In addition, in FIG. 2, the semiconductor element (1) and another member (3) are bonded together in the same plane by an adhesive (4),
Electrode wiring (2) is formed thereon.

In the conventional semiconductor device shown in FIG. 1, in order to use photolithography, the semiconductor element (1) made of a fragile mercury cadmium telluride crystal must be polished to a thin thickness of 10 to 20 Am, and the edges must be etched. This process is very difficult, as it is necessary to create a rounded shape using a rounding method and a lapping method.

In addition, since there are considerable steps, photolithography is extremely difficult.

Furthermore, in the conventional semiconductor device shown in FIG.
) by a method such as lashing.
It is necessary to polish it so that it is flush with the other member (3), which has the disadvantage that the number of steps in the process is extremely difficult and increases.

[Summary of the invention]

This invention was made in order to eliminate the above-mentioned drawbacks, and the semiconductor element and other members such as an insulating plate on which the electrode wiring should be extended are individually adhered to a common insulating substrate, and the semiconductor By extending a thin film from a part of the top surface of the element to a part of the top surface of another member, forming electrode wiring spanning both the semiconductor element and the other member using photolithography technology, and then removing the thin film. The present invention provides a method for manufacturing a semiconductor device that is easy to form and that provides an electrode wiring structure that is not adversely affected by temperature changes after formation.

[Embodiments of the invention]

FIGS. 3(a) and (b) are a side view and a plan view, respectively, showing the state of the method according to the first embodiment of the present invention at an intermediate process stage, and FIGS. 4(a) and (b) are respectively, 1
FIG. 2 is a side view and a plan view of a semiconductor device manufactured by the example method of FIG. First, as shown in FIG. 3, a semiconductor element (1) made of a mercury cadmium telluride crystal and another member (3) such as an insulating plate are placed on an insulating substrate (5) at 150° C. with a gap between them. Adhesively fix with the following low melting point solder (6). Thereafter, a thin film (7) is placed across the gap between a portion of the upper surface of the semiconductor device (1) and a portion of the upper surface of the other member (3). This thin film (7)
It is advisable to use a negative resist that has a certain degree of resistance to organic solvents. At this time, the thin film (7) is attached to the semiconductor element (
1) and other members (3), but if a negative type resist is used for the thin film (7), 10
It was found that annealing for about 15 minutes at around 0°C was sufficient. Thereafter, the electrode wiring (2) is formed by vapor deposition and plating of gold or the like on the part where the turn is to be formed, and then turning is performed by an etching method to form the electrode wiring (2). First, a thin plate made of a polymeric material with a flatness of approximately ±1 μm is prepared.

A negative resist was applied to the surface to a thickness of about 1 μm, and then the negative resist was patterned to the required dimensions by photolithography.

Thereafter, by dissolving the thin plate made of polymeric material with an organic solvent, the required thin film (7) could be obtained. In this case, even if the edges of the semiconductor element (1) and other members (3) are slightly rough, they can still be used in the process, and the adhesive (4) with the conventional structure shown in FIG. No polishing process is required. Furthermore, when performing photolithography, the flatness of the upper surfaces of the semiconductor element (1) and other members (3) is a problem, but when using the method of this invention, the maximum step difference is the thickness of the thin film (7). Since the thickness is approximately 1 μm, it is sufficiently possible to use photolithography, which is very advantageous compared to the conventional structure shown in FIGS. 1 and 2.

Subsequently, the thin film (7) is removed using a resist stripper to obtain the semiconductor device shown in FIGS. 4(a) and 4(b). In other words, if the thin film (7) is left, the thin film (7) will be damaged due to temperature changes during use of this semiconductor element.
In this invention, the thin film (7) is removed because distortion may occur due to the difference in thermal expansion coefficient between the electrode wiring (7) and the electrode wiring (2), resulting in cracks and scratches, resulting in deterioration of characteristics.

FIGS. 5(a) and 5(b) are side views showing the intermediate process stage and completion stage of the second embodiment of the method, respectively, and are essentially the same as the first embodiment. . In this way, to the extent that photolithography is possible, semiconductor elements (
A step may be provided between 1) and the other member (3).

FIGS. 6(a) and 6(b) are side views showing the intermediate process stage and completion stage, respectively, of the third embodiment of the method of the present invention, which are also essentially the same as the first embodiment. Similarly, a thick thin film (7a) may be used within the range where photolithography is possible.

In this way, if the electrode wiring of the semiconductor element (1) can be easily extended onto another member (3) such as an insulating substrate during the lapping process, the substrate of the semiconductor element (1) can be materials that are vulnerable to oxidation, such as mercury-cadmium-telluride crystals. This is because when a bonding pad is formed on these mercury cadmium telluride crystals, the mercury cadmium telluride crystals are altered by the heat and pressure during wire bonding, which directly leads to peeling of the bonding pads. Further, the impact during wire bonding has a negative effect on the active portion of the actual semiconductor element (1), which in turn leads to deterioration of device performance. In order to eliminate these, it is necessary to separate the actual active part and the bonding pad to some extent, and also to make the area of the bonding pad very large. Since mercury cadmium telluride crystals are very expensive, the above-mentioned conventional solution of increasing the area of the bonding pad cannot be said to be preferable from the point of view of trying to utilize it as effectively as possible.

Furthermore, one-dimensional arrays of semiconductor elements (1) using mercury-cadmium-telluride crystals are currently in the stage of practical use, but the one-dimensional arrays require wire bonding for each semiconductor element (1) and other circuits (1). Currently, it is connected to. Therefore, when fabricating a one-dimensional array, the presence of the bonding pad cannot be ignored. Under such conditions, when processing very brittle crystals such as mercury cadmium telluride, no lapping process is required and the bonding pad is placed on the top member (3) on the other insulating substrate. It is believed that this invention, which can form a , will fully exhibit its effects.

〔Effect of the invention〕

As explained above, (1) the present invention is arranged such that a semiconductor element and other members are spaced apart from each other on an insulating substrate, and are bonded together so that the height difference between the surfaces of the semiconductor element and other members is within an allowable value. However, since parts of both surfaces are connected by a thin film, electrode wiring can be formed at the same time using photolithography technology, making the process much simpler than conventional methods and reducing the degree of integration. It gets much better. Additionally, this type of semiconductor device is often cooled to a low temperature before use, but in that case, conventional methods can cause cracks to occur in the semiconductor element due to the difference in thermal expansion coefficient between the semiconductor element and other components. However, according to the method of the present invention, the semiconductor element and other components are supplied only through the electrode wiring, and the thin film used to form the electrode wiring is also removed, so cracks in the semiconductor element can be prevented. It is possible to obtain an extremely excellent semiconductor device without any problem caused by the difference in thermal expansion coefficient between the electrode wiring and the thin film.

[Brief explanation of the drawing]

Figures 1 and 2 show the first diagram of a conventional semiconductor device, respectively.
and a perspective view showing the second example, FIGS. 3(a) and (b)
) are a side view and a plan view respectively showing the state at an intermediate process stage of the method according to the embodiment of this invention, and FIG.
5(b) is a side view and a plan view showing the semiconductor device obtained by the method of this first embodiment, respectively, and FIG. 5(a)
and (b) are side views showing the intermediate process stage and completion stage of the second embodiment of the method, respectively, and FIGS. 6(a) and (b) are respectively the third embodiment of the invention. FIG. 3 is a side view showing the state of the example method at an intermediate process stage and a completion stage. In the figure, (1) is a semiconductor element, (2) is an electrode wiring,
(3) is another member, (5) is an insulating substrate, (7) + (7
a) is a thin film. In addition, the same symbols in the figures indicate the same or corresponding parts.

Claims (4)

[Claims] (1) When manufacturing a semiconductor device having a structure in which the electrode wiring of a semiconductor element extends to the surface of another member, the semiconductor element and the other member are separated from each other with a gap between them, and the upper surface of each are bonded to a common insulating substrate so that the height difference is within an allowable value, and a thin film is provided between each part of both of the upper surfaces by passing over the gap, and the upper surface of the semiconductor element and the other surfaces are bonded to each other. A method of manufacturing a semiconductor device, comprising forming an electrode wiring on the thin film between the thin film and the upper surface of the member, and then removing the thin film. (2) The method of manufacturing a semiconductor device according to claim 1, wherein the semiconductor element uses a brittle semiconductor base material such as mercury cadmium telluride crystal. (3) A method for manufacturing a semiconductor device according to claim 1 or 2, characterized in that a negative resist thin film is used as the thin film. (4) As a method for forming a thin film, a thin polymer plate is used, a negative resist material is thinly applied onto it, and the negative resist material is patterned in the desired manner, and then only the polymer thin plate is dissolved with an organic solvent. 4. The method of manufacturing a semiconductor device according to claim 3, wherein a negative resist thin film is obtained.