JPS6142943A - Manufacture of complex semiconductor device - Google Patents

Abstract

PURPOSE:To improve an ohmic of wiring connected straddling on the surface of both elements by changing a semiconductor element and a function element into an integral structure through an insulating material for each surface of both elements to be the same in height and by forming a fine width wiring straddling on the surface of both elements with a photolithography after forming a metal thin film on the surface of both elements. CONSTITUTION:A surface of an integral structure 12 is fixed on a supporting substrate 1 through a bonding agent 13. The surface leaving a part of an electrode 5 of a semiconductor element 3 is covered with the first resist 14. A metal thin film 15 such as an aluminium is accumulated on a surface of the integral structure 12 including the first resist 14. The first resist 14 and a metal thin film 15 on it are eliminated with the lift off method. The metal thin film 15 left and a desired part of the surface of the electrode 5 is covered with the second resist 16 again, and the metal thin film 15 selectively etched using the second resist 16 as a mask.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a composite semiconductor device in which a semiconductor element and a functional element are arranged on a common support substrate.

By coupling the semiconductor carrier (so-called bulk wave) in each semiconductor element with the surface acoustic wave in the functional surface acoustic wave element, linear coupling such as attenuation and amplification, or non-linear coupling such as convolution and correlation can be achieved. Research and development of surface wave amplifiers, surface wave convolvers, etc. that utilize linear coupling phenomena is being actively conducted.

For this purpose, a semiconductor substrate such as silicon or 1-V group intermetallic compound that constitutes the semiconductor element, a piezoelectric substrate such as lithium niobate (LtNbO3) or lithium tantalate (LiTa0a), and Z Figure 7 is obtained in this way and shows the structure of a composite semiconductor device, where 5 is a support substrate, 2 is a lead, 3 is a semiconductor element, and 4 is a surface acoustic wave. element,
・5 and 6 are 1! provided on the 3゜4 surface of the above element, respectively. A pole 7 is a bonding wire that connects the electrodes 5 and 6 or between the electrodes 5 and 6 and the lead 2. The semiconductor element 3 and the surface acoustic wave element 4 are arranged on a support substrate l.

However, there are manufacturing problems in integrally combining the substrates χ made of different materials in this way.

For example, the electrode 6 formed on the surface of the surface acoustic wave element 4 is for producing a surface acoustic wave element called a transducer, which is provided in a webbing shape with a pattern width of 1 to 2 microns, and is made of aluminum or the like. , - On the surface of the male conductor element 3, an electrode 5 with a width of 5 to 6 micrometers is formed, and the electrodes 5 and 6 are connected by the bonding wire 7, as described above. It is extremely difficult to perform good wire bonding between 'FiL&'. Therefore, a special process has to be adopted, which increases costs.

The present invention has been made in response to the above problems, and is a composite semiconductor device configured to easily form wiring spanning the surfaces of semiconductor elements and functional elements (without employing special processes). The purpose of the present invention is to provide a method for manufacturing the same.

The features of the present invention for achieving such objects are as follows: (A) a step of integrating the semiconductor element and the functional element with an insulator interposed so that their respective surfaces are at the same height;
a step of forming a first resist so as to cover a desired portion of the surface of the semiconductor element in the integrated structure; a step of forming a metal R film on the surface of the integrated structure including the resist of (E)il; a step of removing a portion of the thin film; (E) a step of forming a second resist so as to cover a desired portion of the metal thin film and the surface of the semiconductor element;
F) A method for manufacturing a composite semiconductor device, including the step of forming a wiring 161a' spanning the surfaces of a semiconductor element and a functional element by selectively removing a metal thin film as a M2 resist If' mask. It is.

Is the drawing below? Implement the present invention with reference to ν! I'a [to clarify.

FIG. 2 (ω to (g) are cross-sectional views showing the manufacturing method of a composite semiconductor device according to an embodiment of the present invention in the order of steps, and will be explained below in order of process J. ◎ Step [A]: The steps in FIG. 2(a) A film 9 is prepared on a support base 8, and a desired circuit element is provided on this film 9, and a cylindrical element 3 having an electrode 5 and an elastic surface element 4 made of a piezoelectric substrate are connected with a gap lO. The insulating connection part 11 is formed in the gap 10. That is, with the pixel elements 3 and 4 as close as possible, for example, a resin is injected into the gap 10 and cured, and then the film 9 is peeled off. .

As a result, an integrated structure 12 consisting of the semiconductor element 3 and the elastic surface V element 4 which are arranged via the insulating connection part 11 so that their surfaces are at the same height is obtained.

Step [8]: As shown in FIG. 2(b), the above integrated structure 1
The back surface χ of No. 2 is fixed onto the support substrate l via the adhesive 13'4. Next, a portion χ of the electrode 5 of the semiconductor element 3 is left and its surface 7 is coated with a first resist 14 made of, for example, a positive type resist by a well-known photolithography method.

Step [C]: As shown in FIG. 2(c), 1115 g of a thin metal such as aluminum is deposited on the surface of the integrated structure 12 including the first resist 14 by vapor deposition, sputtering, or the like. In this case, since the thickness of the first resist 14 is considerably larger than the thickness of the electrode 5 of the semiconductor element 3,
The thickness of the metal thin film 15 deposited on this stepped portion is smaller than on the other portions.

Step [D]: As shown in FIG. 2(d), the first resist 14 and the overlying metal thin layer [15 mm] are removed by a well-known lift-off method. The metal thin film 15 remains so as to straddle a part of the electrode 5 and the surfaces of the surface acoustic wave element 4.

Step [E): As shown in FIG. 2(e), the remaining metal thin film 15 and electrode 5 are removed by photolithography again.
A desired portion of the surface is covered with a second resist 16.

As shown in the top view in FIG. 2, the desired portions to be covered with the second resist 16 are the semiconductor element 3 and the metal thin film layer extending from the electrode 5.

Step [F]: As shown in FIG. 2 (gl), the second resist 16 is used as a mask to selectively etch the metal thin film 15i.
Semiconductor element 1 of 3! A tile distribution gland 17 is obtained spanning the surfaces of the pole 5 and the surface acoustic wave element 4.

At this time, interdigital electrodes 6 can be formed on the surface of the surface acoustic wave element 4 at the same time.

If the photolithography method is used to form an arrangement 1iIye spanning the pixel elements, the width of the wiring will be determined by the processing accuracy of the IJ Sogelafy method, and the width of the wiring will be approximately 1μ. Because you can get
It becomes possible to form the interdigital electrodes and the electrodes at the same time.

The type a resists used in photolithography are not limited to positive types, but negative types can be used as well.

Further, the functional element is not limited to a surface acoustic wave element.

As is clear from the above description, according to the present invention, a semiconductor element and a functional element are integrated with each other via an insulator so that their surfaces are at the same height, and a metal thin film is formed on the surface of the pixel element.
After formation, the structure is such that a fine-width wiring that spans the pixel surface is formed using the photophosphorography method Z, so it is possible to create a composite medium conductor device without using special processes as in the past. can be easily manufactured.

Therefore, it is possible to reduce the cost and improve the ohmic characteristics of the wiring connected across the surface of the pixel element, so that a composite semiconductor device TV with excellent performance can be obtained.

[Brief explanation of drawings]

Fig. 1 is a perspective view for explaining the present invention, Fig. 2(a)
to (- are examples of the present invention) are cross-sectional views and top views shown in the order of steps. 1...Support substrate, 3...Semiconductor element, 4...Surface acoustic wave element (functional element), 5, 6 ...is pole, 8...
Support stand, 9... Film, 10... Gap, 11...
・Insulating connection part, member...integrated structure, 13...adhesive, 14.16...resist, 15...metal thin film, 1
6...Wiring. Figure 1 Figure 2 Figure 2

Claims (1)

[Claims] 1. (A) A step of integrating a semiconductor element and a functional element via an insulator so that their surfaces are at the same height; (B) A desired portion of the surface of the semiconductor element in the integrated structure. (C) forming a metal thin film on the surface of the integrated structure including the first resist; (D) removing a part of the metal thin film together with the first resist; (E) forming a second resist so as to cover the remaining metal thin film and a desired portion of the surface of the semiconductor element; (F) selectively removing the metal thin film using the second resist as a mask; 1. A method for manufacturing a composite semiconductor device, comprising the step of forming wiring spanning the surfaces of an element and a functional element. 2. The above step (B) consists of a step of forming a first resist so as to cover all but a portion of the electrode surface of the semiconductor element in the integrated structure, and the above step (F) consists of forming a first resist using the second resist as a mask. The composite according to claim 1, comprising the step of selectively removing a metal thin film to form a wiring that spans a part of the electrode surface of the semiconductor element and the surface of the functional element. A method for manufacturing a semiconductor device. 3. The method for manufacturing a composite semiconductor device according to claim 1 or 2, wherein the functional element is a surface acoustic wave element.