JPH05183680A - Close contact type image sensor unit - Google Patents

Abstract

PURPOSE:To provide the simple, compact and inexpensive close contact type image sensor unit in which a semiconductor image sensor element is mounted on a printed circuit board simply in a short time, a convergent rod lens is assembled with no adjustment and an original is read with high resolution. CONSTITUTION:A semiconductor image sensor having a light receiving element array 6 is mounted on the surface of a 1st light transmission board 1 on the surface of which a circuit conductor layer 2 is formed via a light curing type insulation resin 5 in a face-down way so that its electrode 4 and the circuit conductor layer 2 are pressed into contact. A convergent rod lens array 7 placed between light transparent plates 8 is mounted on the rear side of the said 1st light transparent board 1 and a 2nd light transparent board 9 with the same thickness as the 1st light transparent board 1 is mounted on the rear side furthermore the rear side of the 2nd light transparent board 9 is used for an original close contact face and the original is lighted from the upper part with a light source (LED array) 10 to read the original.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contact image sensor unit for converting an optical image into an electric signal.

[0002]

2. Description of the Related Art Conventionally, in a contact type image sensor unit, a semiconductor element 22 including a light receiving element array 31 is fixed on a substrate 21 on which conductor wiring is formed in FIG. 29 and the circuit conductor layer 28 are connected by a metal thin wire 30 such as gold or aluminum by a wire bonding method, and further sealed with a transparent glass sealing material 23 to produce an image sensor. The LED array 25 (light source) and the converging rod lens 24 had to be three-dimensionally assembled and adjusted to the holder 27.

[0003]

However, in the above-mentioned structure, a complicated process such as wire bonding is required, and the focusing rod lens is position-adjusted and incorporated into the image sensor when the image sensor unit is manufactured. There was a problem that it was necessary.

[0004]

In order to solve the above-mentioned problems, the present invention provides a first light-transmissive substrate having a circuit conductor layer formed on the surface thereof with a light-receiving element array via a photo-curable insulating resin. An image sensor is created by mounting the semiconductor element having the element face down so that the extraction electrode formed on the element is in contact with the circuit conductor layer, and a focusing rod lens array and a converging rod lens array are provided on the back surface of the image sensor. A second light-transmissive substrate having the same thickness as the first light-transmissive substrate is adhered, and the back surface of the second light-transmissive substrate is used as a document contact surface to produce a contact image sensor unit having a structure in which illumination is applied from above the semiconductor element. is there.

[0005]

With the above-described structure, the present invention realizes a simple, compact and high-performance contact type image sensor unit which does not require position adjustment and can read a document with high resolution.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A contact image sensor unit according to an embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a front sectional view of a contact image sensor unit according to an embodiment of the present invention.
Reference numeral 1 is a first transparent substrate, 2 is a circuit conductor layer formed on the surface of the first transparent substrate 3, 3 is a semiconductor image sensor element used as a semiconductor image sensor element, and 4 is a semiconductor image sensor element 3. , 5 is a transparent photo-curable insulating resin for mounting the semiconductor image sensor element 3 on the first transparent substrate 1, 6 is a light receiving element array provided in the semiconductor image sensor element 3, 7 is a focusing rod lens array mounted on the back surface of the first transparent substrate 1,
Reference numeral 8 is a side surface of the converging rod lens array 7 and a translucent plate provided on the back surface of the first translucent substrate 1, and 9 is a second side mounted on the back surfaces of the converging rod lens array 7 and the translucent plate 8. A transparent substrate 10 is an LED array that illuminates the original 11 through the first transparent substrate 1, the transparent plate 8 and the second transparent substrate 9.

A method of manufacturing the contact type image sensor unit having the above structure will be described.

First, a light receiving element array 6 such as a phototransistor or a photodiode and a CCD or a MOS are formed on a single crystal silicon substrate (wafer) by using a semiconductor process.
An access circuit (not shown) such as a bipolar IC is provided. Each electrode 4 has a structure in which it protrudes from the wafer surface by about several μm by a sputtering method using a two-layer Al wiring process. After that, this wafer is cut by a high-precision dicing technique to make a semiconductor image sensor element 3. Next, on the surface of the first translucent substrate 1 made of glass having a thickness of about 1.1 mm, a metal such as Au or Ag is used to form the circuit conductor layer 2 with a thickness of 3 μm to 10 μm by thick film printing. Form. An acrylate-based transparent photo-curable insulating resin 5 is applied to a predetermined position of the light-transmissive substrate 1 in a predetermined amount by a stamping method, a screen printing method, or the like, and a semiconductor image sensor element 3 and an electrode 4 having a predetermined electrode are applied thereon. It is arranged face down so as to contact the circuit conductor layer 2. After that, while applying a predetermined pressure from above the semiconductor image sensor element 3, the transparent photocurable insulating resin 5 is irradiated with ultraviolet rays through the transparent substrate 1 to be cured and the mounting is completed. Further, a resin such as transparent silicone is applied from above with a dispenser or the like to form a protective layer (not shown) to manufacture an image sensor.

Further, a converging rod lens array 7 sandwiched between translucent plates 8 is mounted on the back surface of the first translucent substrate 1 of this image sensor with a transparent adhesive, and the back surface thereof has the first translucent property. A second light-transmissive substrate 9 made of glass and having the same thickness (1.1 mm) as the substrate 1 is mounted using the same transparent adhesive. Finally, the LED array 10 is arranged in a close position above the image sensor. In this way, the contact image sensor unit is completed.

Regarding the operation principle of the contact type image sensor unit of the present invention, the LED array 10 includes a first transparent substrate 1, a transparent plate 8 and a second transparent substrate 9.
The document 11 is illuminated through the light source, and the light information from the document is guided to the light receiving element array 6 by the converging rod lens 7 at an erecting equal-magnification ratio and converted into an electric signal.

In the semiconductor image sensor element used here, a phototransistor is used as a light receiving element array,
A bipolar IC chip using a thyristor shift register is adopted for the scanning circuit.

As described above, the focusing rod lens array 7
The contact type image sensor unit of the present invention assembled without adjustment had a high MTF (modulation-transfer-function) value of about 60% (4 lp / mm).

[0014]

As described above, according to the image sensor unit of the present invention, the semiconductor image sensor element is not subjected to the wiring (wire bonding) work with a complicated metal thin wire,
Further, even in the case of a semiconductor element, it can be mounted with high reliability on a light-transmissive substrate provided with a circuit conductor layer without forming bump electrodes, and assembling a focusing rod lens or the like without optical adjustment. Can be very simple,
The original is compact and can be read at low cost.

[Brief description of drawings]

FIG. 1 is a front sectional view of a contact image sensor according to an embodiment of the first invention.

FIG. 2 is a front sectional view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st translucent board 2 Circuit conductor layer 3 Semiconductor image sensor element 4 Electrode 5 Transparent light hardening type insulating resin 6 Light receiving element array 7 Focusing rod lens array 8 Translucent plate 9 2nd translucent substrate 10 LED array DESCRIPTION OF SYMBOLS 11 manuscript 21 substrate 22 semiconductor image sensor element 23 glass sealing material 24 converging rod lens array 25 LED array 26 manuscript 27 holder 28 circuit conductor layer 29 semiconductor element electrode 30 metal fine wire 31 light receiving element array

Claims (3)

[Claims] 1. A semiconductor device comprising: a first light-transmitting substrate having a circuit conductor layer formed on a surface thereof; and a semiconductor element having a light-receiving element array on the surface of the first light-transmitting substrate. Is a face-down structure in which the extraction electrode formed on the element is in contact with the circuit conductor layer, and on the back surface of the transparent substrate, a focusing lot lens array corresponding to the light receiving element array is formed. Mounted on the back side,
A contact-type image sensor unit in which a second light-transmissive substrate is mounted, a back surface of the second light-transmissive substrate is used as a document contact surface, and a light source is provided above the semiconductor element. 2. The contact type image sensor unit according to claim 1, wherein a transparent photo-curable insulating resin is used to mount the semiconductor element having the light receiving element array on the surface of the first transparent substrate. 3. The contact image sensor unit according to claim 1, wherein the first transparent substrate and the second transparent substrate have the same thickness.