JPS6346762A - Semiconductor device - Google Patents

Abstract

PURPOSE:To obtain twice semiconductor elements from one transparent substrate by using the transparent substrate as an insulating substrate, observing a scribing region formed on one side surface through from the other side surface, and bringing it into coincidence with both side surfaces through the substrate to form semiconductor elements on both side surfaces of the substrate. CONSTITUTION:An insulating substrate is used as a transparent substrate 1, a scribing line 7 region formed on one side surface is observed through from the other side surface, and the scribing line 7 regions are brought into coincidence with both side surfaces through the substrate 1 to form semiconductor elements 6 on both side surfaces. That is, the line 7 is commonly formed to form the elements 65 on both front and rear surfaces of the substrate 1, and the elements 6 are executed for operation tests after a series of semiconductor processing steps are finished, and scribed to be divided, and only the elements of good products are used. Accordingly, most of the processing steps of the semiconductor, such as growing, annealing, oxidizing and etching of a polycrystalline Si by CVD can be simultaneously executed for both front and rear surfaces of the substrate 1. Thus, the number of the steps is not almost increased to obtain twice the elements 6 as large as the conventional case from one substrate 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a semiconductor device, and particularly to a large-area semiconductor device that can be manufactured with high yield.

[Summary of the invention]

The present invention provides a semiconductor device in which a semiconductor layer is formed on an insulating substrate and a plurality of semiconductor elements are formed in the semiconductor layer. The substrate is a transparent substrate, a scribe line area formed on one side is seen through from the other side, the scribe areas are aligned on both sides through the substrate, and the semiconductor element is formed on both sides of the substrate, It is an object of the present invention to provide a semiconductor device manufactured with high yield.

[Conventional technology]

Semiconductor devices that play the role of man-machine interfaces, such as liquid crystal display devices, thermal heads, and image sensors, inevitably have a large pellet size.

For example, a 2-inch color television liquid crystal display device has as many as 70,000 transistors built into a 3 x 4 cm area. These semiconductor devices are formed by providing an A-3I or polycrystalline Si layer on one side of a 5-inch or 6-inch quartz and building tens of thousands of transistors therein. A TV screen is created by each transistor controlling the voltage applied to the liquid crystal forming each picture element.

[Problem that the invention seeks to solve]

The yield of semiconductor devices improves as the area occupied by one half-dimensional element becomes smaller.

Semiconductor elements for man-machine interfaces are several tens of times larger than ICs such as ordinary DRAMs, so even if semiconductor elements for man-machine interfaces are made of amorphous materials, they cannot be fabricated on single-crystal substrates. Even if the characteristics of the semiconductor device to be formed are not as good as that of the semiconductor device being formed, it is extremely difficult to improve the manufacturing yield. For example, in the case of a color television liquid crystal display device, out of 70,000 elements, only 5 transistors are allowed as defective. This is because when a defective transistor occurs, the pixel in which the transistor is located stops working, and that point becomes the only white dot in the changing image, resulting in an extremely unsightly screen. However, although it is not impossible to reduce the number of defective transistors to less than five using current manufacturing technology, the cost increases accordingly. Therefore, adjustments have been made between the two, and currently, in the case of liquid crystal display devices for 2-inch color televisions, devices with 5 or fewer defective transistors are considered to be good products.

Actually, six of these elements (one piece: 3×4 cm) are formed on a 6-inch quartz plate 1, as shown in FIG.

However, even if six transistors are formed, all six transistors will not be good (with five or fewer defective transistors), and the elements with about three transistors will be defective. Improving this yield is a very important factor in lowering product prices.

[Failure to solve the problem]

The present invention relates to a semiconductor device in which a semiconductor layer is formed on a substrate and a plurality of semiconductor elements are formed on the semiconductor layer. The second problem was solved by viewing the area from another side, making the scribe area pass through the substrate on both sides, and forming the semiconductor element on both sides of the substrate.

[Effect]

In the present invention, semiconductor elements are formed on the front and back sides of a transparent substrate using a common scribe line, and after a series of semiconductor processing steps are completed, an operation test is performed on each semiconductor element, and the scribe is divided to determine whether the semiconductor element is good. It is used only.

Growth of polycrystalline Si by CVD, annealing, oxidation,
Many semiconductor processing steps, such as etching, can be performed on both the front and back surfaces of a substrate at the same time.

Therefore, compared to a conventional semiconductor device that uses only one side of a quartz substrate, the semiconductor device of the present invention can produce twice as many semiconductors from a single substrate without increasing the number of steps. element can be obtained.

In addition, although quartz used in the semiconductor industry has optical flat processing on both sides, it is wasteful to use only one side of the quartz plate as in the past, and even if both sides are processed at the same time, the overall The present invention was developed based on the recognition that twice the number of semiconductor devices can be obtained without significantly increasing the number of processing steps, and as a result, the yield per substrate can be improved.

If the element on the front side of the scribe-divided pellet is good and the element on the back side is defective, the element on the back side is ignored and the element on the front side is mounted in a predetermined position.

Each picture element has a 140 μm opening, and the area occupied by the transistor therein is about 1χ, so the presence of the transistor on the back side does not have an adverse effect on the element on the front side, and there is no need to take the trouble to remove the semiconductor element on the back side.

〔Example〕

The semiconductor device of the present invention will be explained based on its manufacturing process with reference to FIGS. 1A to 1M. In these drawings, the dimensions of elements, layers, etc. are not drawn to scale. In particular, the width of the scribe line 7 is only 20 μm, but for convenience, each semiconductor element is drawn separately in these drawings.

A: Polycrystalline 5i62 is grown on both sides of a quartz substrate 1 with a thickness of 800 μm and a diameter of 6 inches by a low pressure vapor phase growth method.

B. A photoresist layer 3 is provided on one side, and patterning is performed to obtain six semiconductor elements.

A photoresist layer 3 is also provided on the CG surface, and a pattern is formed at the same position as the front side batten so that the scribe line is at the same position on the front and back sides. Since the substrate 1 is a transparent quartz plate, the positions of the patterns on the front and back sides can be easily adjusted.

D Etch the polycrystalline Si layer 2 using photoresist patterns 3 provided on the front and back sides.

E. A SiO□ layer 4 is formed as a gate oxide film on the front and back sides simultaneously by low pressure vapor phase epitaxy.

Polycrystalline 5i5s (F gate electrode) is formed simultaneously on the front and back sides.

All of the following processes are performed simultaneously on the front and back sides.

G. Etching the polycrystalline Si layer 5 S2 forms the gate electrode of each transistor.

11. Source/drain regions are formed in the polycrystalline Si layer 4 by ion implantation using the polycrystalline Si gate electrode as a mask.

I. Grow a SiO□ film.

J Form a contact hole for a wiring electrode in a 5in2 film.

Wiring electrodes are formed by sputtering K Al metal.

L A 5iJn film is formed as a panshidion film by plasma CVD method.

M Form a contact hole in the bonding band,
After performing an operation test on each semiconductor element and identifying a defective semiconductor element, scribing is performed.

By using these manufacturing methods, a 6-inch quartz-based liquid crystal drive device for a 2-inch color TV with a size of 3 x 4 cm can be produced! Fi1
You can get 12 pieces per sheet. Even if the yield is 50%, six good semiconductor devices can be obtained from one quartz substrate.

Note that a multi-stack chip is constructed by gluing the pellet with devices formed on both sides in this manner onto another LSI chip, connecting the lower device to the base chip, and wire bonding the upper device. You can also do that.

〔Effect of the invention〕

With the semiconductor device of the present invention, twice as many semiconductor elements can be obtained from one transparent substrate with almost no change in the number of steps compared to conventional manufacturing methods, resulting in a reduction in the number of semiconductor elements per substrate. The retention rate can be significantly improved.

[Brief explanation of drawings]

1A to 1M show the manufacturing process of a semiconductor device of the present invention. FIG. 2 shows a semiconductor element on a substrate.

Claims (1)

[Claims] In a semiconductor device in which a semiconductor layer is formed on an insulating substrate and a plurality of semiconductor elements are formed on the semiconductor layer, a transparent substrate is used as the insulating substrate, and a scribe region formed on one surface is seen through from the other surface. A semiconductor device, wherein the scribe areas are aligned on both sides with the substrate interposed therebetween, and the semiconductor element is formed on both sides of the substrate.