JPS6110264A - Manufacture of hybrid ic - Google Patents

Abstract

PURPOSE:To enable successive film formation of a Ta series thin film used as the resistor and a Ta series thin film used as the capacitor, by a method wherein the atmosphere in film formation of a Ta series thin film is varied as required. CONSTITUTION:A TaN thin film 3 having a necessary resistivity is sputtered on an insulation substrate 1 coated with a tantalum oxide film 2, and a Ta thin film 4 is successively sputtered. Next, a window is opened at the position corresponding to a resistance element 6 after coat of photo resist 5; thereafter, the Ta layer 4 is changed into an oxide 4a by anodic oxidation. After removal of the photo resist 5, the parts of the lower electrode of the capacitor, its lead-out conductive path 9, and a lead-out conductive path 8 of a resistor terminal are formed into pattern. A photo resist 10 is applied, then a window is opened at the part of the lower electrode, and an oxide film 7 having a necessary withstand voltage is formed by anodic oxidation. After removal of the photo resist, dichromium, palladium, and gold thereon are formed into film, and the pattern of conductor paths 11, 13 and the upper electrode 12 of the capacitor is formed.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a method of manufacturing a thin film hybrid integrated circuit including a capacitor and a resistive element.

mouth, conventional technology Tantalum (Ta) thin film integrated circuits are made of alumina.

A Ta thin film and a tantalum nitride (TaN) thin film are fabricated on an insulating substrate such as glass, and these are used to fabricate capacitors,
It forms an electronic circuit that includes passive elements such as resistors.
By changing the atmosphere when depositing Ta, pure Ta can be formed.
, or a TaN thin film 2 can be made.

Conventionally, when a capacitor and a resistor are formed using one type of Ta-based thin film, the characteristics of the Ta-based thin film used are fixed, which limits the flexibility in circuit design. This is because the Ta-based thin film used as a capacitor and the Ta-based thin film used as a resistor do not have the same required characteristics.

Therefore, when forming a capacitor and a resistor on the same substrate, conventionally at least two types of Ta-based thin films have been separately formed to form elements.

C.6 Problems to be Solved by the Invention Separately manufacturing capacitors and resistors by separately forming two types of Ta-based thin films as described above has the disadvantage that it takes a long time to manufacture.

21 Technical Means for Solving the Problems The present invention provides a solution to the Ta-based thin film used as a resistor by changing the atmosphere when forming a Ta-based thin film as necessary.
By successively forming a Ta-based thin film and a Ta-based thin film used as a capacitor, the thin film integrated circuit in which a capacitor and a resistor with desired characteristics are formed on the same substrate can be made as short as possible. Realized in manufacturing time.

E, Example Next, the present invention will be explained by examples.

Fig. 1(a) to te)r$ First, Fig. 1(a)
As shown in FIG. 2, a TaN thin film 3 having the required resistivity is sputtered over the entire surface of an insulating substrate 1 made of alumina, glass, etc. covered with a tantalum oxide film 2, and subsequently, during the same pumping cycle, Ta thin film 4 with a thickness of about 200OA
Sputter continuously. Next, as shown in FIG. tb), a photoresist 5 is applied over the entire surface of the substrate by a known method such as spin coating, and a window is opened at a position corresponding to a resistive element 6. After that, a Ta layer 4 is formed by anodizing. Convert to oxide 4a. Next, as shown in FIG. 5C, after removing the photoresist 5, the lower electrode of the capacitor and its lead-out conductive path 9 and the glass lead-out conductive path 8 of the resistor are etched using a known photolithography technique. A pattern is formed by At this time, the oxide film 4a on the resistance element 6 is
Since it acts as an etching-resistant layer in the process of etching the TaN--Ta film, the required pattern of the resistor element can be formed with high precision. Next, as shown in the same figure (d), after applying 1 lot of photoresist over the entire surface of the substrate,
A window is opened in the lower electrode portion of the capacitor, and an oxide film 7 having the necessary withstand voltage is formed by anodic oxidation.

That is, the surface of the "I'a thin film of about 200 OA is converted into an insulating layer of Ta!05 by chemical conversion treatment. For example,
If a voltage of 150V is applied and chemical conversion is performed, the output will be approximately 75OA.
of Ta thin film is consumed, and this is about 300 OA thick Ta thin film! 06 thin film, which acts as the dielectric of the capacitor, as shown in the same figure (e).

Photoresist removal technique, nichrome (N
iCr) to a film thickness of approximately 1oooA, followed by palladium (
Pd) to a film thickness of about 100OA, and gold (A
After forming a film (U) to a thickness of about 600 OA by magnetron sputtering, patterns for the conductor paths 11, 13 and the upper electrode 120 of the capacitor are formed by photolithography.

Here, NiCr acts as an adhesion layer with the base, Pd acts as a Cr diffusion prevention layer during the subsequent stabilization heat treatment, and Au acts as a layer to reduce conductor resistance and to provide adhesion to the external glass. It is made in order to make it last. Next, the thin film integrated circuit formed in this way is heat treated in the atmosphere at 120°C to 200°C, and then the device formation is completed by adjusting each element constant to the target value using a laser trimming method. .

Effects of the Invention The present invention is advantageous because, in the conventional element forming process for thin film integrated circuits, sputtering and patterning of at least two types of Ta-based thin films for capacitors and resistors were performed separately. However, by changing the atmosphere in which the film is formed in a single sputtering process, we were able to use a Ta-based thin film with a multilayer structure for resistors and capacitors, and to create a selective anode. By combining oxidation methods, it is possible to form capacitors and resistors on the same substrate with a minimum number of steps.

By applying the present invention, a thin film integrated circuit in which a capacitor and a resistor having desired characteristics are formed on the same substrate can be manufactured in a short time.

In the above embodiment, the element is formed of a two-layer film using TaN as the resistor l- and Ta as the capacitor layer, but the present invention does not limit the materials used to the above materials. Metal with.

The present invention can be applied to multilayer thin films made of alloys or metal compounds.

[Brief explanation of drawings]

FIGS. 1A to 1E are cross-sectional views sequentially showing each step of a manufacturing method according to an embodiment of the present invention. 1...Insulating substrate, 2...Tantalum oxide film, 3...Tantalum nitride thin film, 4...
...Tantalum thin film, 4a...Tantalum oxide, 5.10...Photoresist, 6...
・S(resistance element, 7... dielectric of bow capacitor, 8.
9... Tantalum conductive path, 11... Resistor lead lead conductive path, 12... Capacitor upper electrode, 13... Capacitor lower electrode lead lead conductive path.

Claims (1)

[Claims] a step of successively forming at least two types of thin films having valve action on an insulating substrate; a step of selectively oxidizing at least one layer of the multilayer thin film to form a resistance pattern; It is characterized by comprising a step of selectively removing a part of the unoxidized portion of the thin film, and a step of selectively oxidizing the surface of the unoxidized portion that was not removed to convert it into a dielectric layer of a capacitor element. A method for manufacturing a thin film hybrid integrated circuit.