TWI473982B - Infrared sensing chip - Google Patents

Description

Infrared sensing chip

The present invention relates to an infrared sensing wafer, and more particularly to an infrared sensing wafer that is activated by a pyroelectric principle and integrated with an integrated circuit into a single wafer.

Since the discovery of infrared rays, after years of research and development, infrared rays have been gradually applied to various fields. For example, infrared sensors are used to detect the heat radiation of an object, thereby monitoring the temperature change of the object without touching the object. Further, it is better to recognize the position and dynamics of objects in the dark.

The infrared sensor can be mainly divided into two types: quantum type and hot type. The sensing principle of the quantum type sensor is to absorb the infrared energy to make the sensing material (such as the photodiode composed of cadmium sulfide and lead sulfide). Free carriers are generated to detect energy intensity, while quantum sensors have two main advantages: high sensitivity and fast response time. The disadvantage is that low temperature refrigeration system is needed to reduce the operating temperature of the sensing system. To reduce the interference of the ambient background temperature.

When the heat sensor absorbs the energy of infrared rays, it can change the temperature of the sensing element and change the physical properties of the material itself, such as resistance, which is also called the principle of pyroelectricity. The sensitivity and response time of the thermal sensor are not as good as the quantum sensor, but the thermal sensor can The operation is at room temperature and does not require the assistance of a cooling system. In addition, the thermal sensor has a wide absorption spectrum and is flat, making it suitable for power-saving and portable applications.

In general, in order to improve the sensitivity of the thermal sensor, a material having a high temperature coefficient of resistance (TCR) is selected as the sensing element, and a common high temperature coefficient of resistance material is mercury halide. Cadmium (HgCdTe) or vanadium oxide (V ₂ O ₅ ), but the material cost of these materials is high, and the process is usually not integrated into the integrated circuit process. The far-infrared sensing element and the transistor that converts the electrical signal must be converted. After the wafer is separately fabricated, the sensing element is electrically connected to the transistor by bonding. In addition to the fact that the volume of the overall sensor is not easily reduced, the bonding technique is also one of the problems leading to the instability of the yield. .

In recent years, with the advancement of process and microelectromechanical technology, infrared sensing components and circuit reading components can be integrated into a single wafer process. As shown in FIG. 1, an infrared sensor disclosed in Taiwan Patent Application No. 098132569 (hereinafter referred to as "the 256 case") uses an integrated circuit process to form a transistor region A2 on a substrate 1a and has an infrared detecting element. Infrared sensing area A1 of 13, the infrared detecting element 13 includes an absorption unit 131 for absorbing infrared rays, a temperature sensing body 132 for sensing infrared rays and having pyroelectric characteristics on the absorption unit 131, and a The compensation film structure 133 on the temperature sensing body 132; further, the germanium substrate 1a further includes a pair of voids 11 formed by the position of the temperature sensing body 132, and the absorption unit 131 is composed of a tantalum oxide film and a tantalum nitride film. And the temperature sensing body 132 is made of polysilicon, so from the use of materials, "256 cases can indeed In order to integrate the infrared sensing element with the process of the transistor element, it must be combined with other designs, such as the absorption unit 131 that increases infrared absorption and the effect of improving the heat insulation, and avoiding the heat of the temperature sensing body 132 being dissipated too quickly, resulting in a weakened signal hole. 11 and other structures to enhance the sensitivity, and a large technical feature of the "256 case is that the absorption unit 131 and the temperature sensing body 132 are protected by the compensation film structure 133 composed of a polysilicon film, and the absorption unit 131 is suppressed. The film layer of the temperature sensing body 132 is warped to improve structural stability and improve sensing efficiency.

Although this "256 case teaches the possibility of component integration, how to further improve the overall structure of the sensor and reduce the cost to meet market demand and improve market competitiveness based on the premise of process integration, is the applicant's desire to develop research. One of the directions.

Accordingly, it is an object of the present invention to provide an infrared sensing wafer that can be integrated into an integrated circuit and that is easy to use and carry.

Furthermore, another object of the present invention is to provide an infrared sensing wafer which can be integrated into a single-wafer and can be used and carried conveniently with a 2P integrated circuit process.

Therefore, the infrared sensing chip of the present invention is for detecting an infrared ray having a wavelength of λ, and comprises a wafer substrate, a patterned polysilicon layer and an interconnect unit.

The wafer substrate is comprised of a semiconductor material and includes a top surface and a bottom surface opposite the top surface.

The patterned polysilicon layer is located on a top surface of the wafer substrate, defines a transistor structure region and an infrared absorption region, and the transistor structure region Forming a plurality of convertible electrical signal transistor units in cooperation with the wafer substrate, the infrared absorbing region comprising a body portion and two electrical pin ends connected to the body portion and spaced apart, the body portion absorbing incident A change in resistance is generated after the infrared rays are electrically connected to the corresponding transistor unit via the ends of the electrical pins, and the resistance change is converted into an electrical signal output through the transistors.

The interconnecting unit is disposed on the wafer substrate and the patterned polysilicon layer, and includes a plurality of metal layers in a predetermined electrical connection pattern and an opening for the infrared light to enter the infrared absorption region, wherein a metal layer has a a reflective block directly above the main body portion, the reflective block cooperates with the main body portion to define a cavity, the cavity is connected to the outside to allow infrared rays to enter the cavity, and the lower surface of the reflective block reaches the The distance from the top surface of one of the main portions of the infrared absorption region is (2n+1)λ/4, and n is a positive integer or zero.

In addition, the infrared sensing chip of the present invention is configured to detect an infrared ray having a wavelength of λ, and includes a wafer substrate, a first patterned polysilicon layer, a second patterned polysilicon layer, and an interconnect unit.

The wafer substrate is composed of a semiconductor material.

The first patterned polysilicon layer is located on the surface of the wafer substrate, defines a transistor structure region and a first infrared absorption region, and the transistor structure region cooperates with the wafer substrate to form a plurality of convertible electrical signals. a crystal unit, the first infrared absorbing region includes a main body portion and two electric pin ends connected to the main body portion, and the main body portion absorbs incident infrared rays to generate a resistance change, and the electric pin ends through the electric terminals Department and corresponding The electrical connection of the transistor unit causes the change in resistance to be converted to an electrical signal output through the transistor unit.

The second patterned polysilicon layer is formed on the first patterned polysilicon layer, and includes a second infrared absorption region above the first infrared absorption region and at least one through hole extending through the second infrared absorption region. The second infrared absorption region absorbs infrared rays to generate a resistance change and is electrically connected to the corresponding transistor unit to cause the resistance change to be converted into an electrical signal output through the transistor unit, and the perforation causes the incident infrared rays to pass through The main body portion of the first infrared absorption region.

The interconnecting unit is located on the surface of the wafer substrate, and includes a plurality of metal layers in a predetermined electrical connection arrangement pattern, and an opening for injecting infrared rays into the second infrared absorption region, wherein a metal layer has a second layer a reflective block directly above the infrared absorption region, the reflective block and the second infrared absorption region cooperate to define a cavity, the cavity is connected to the opening to allow infrared energy to enter the cavity, and the reflective block The distance from the surface to the top surface of the body portion of the infrared absorption region is (2n+1)λ/4, and n is a positive integer or zero.

The effect of the invention is that the selection and structure design of the material allows the absorption layer for sensing infrared rays to be fabricated together with the same integrated circuit process of the transistor unit, and the incident height is controlled by the height control of the cavity. The infrared rays form resonance, improve the absorption efficiency of infrared rays, and maintain the sensitivity of the infrared sensing wafer of the present invention while reducing the process cost.

2‧‧‧ Wafer substrate

41‧‧‧metal layer

21‧‧‧ top surface

41a‧‧‧First metal layer

22‧‧‧ bottom

41b‧‧‧Second metal layer

23‧‧‧ Inner torus

411‧‧‧Reflecting block

24‧‧‧ base

412‧‧‧Auxiliary etching tunnel

20‧‧‧Second resonant cavity

410‧‧‧ cavity

3‧‧‧ patterned polycrystalline layer

42‧‧‧Dielectric layer

31‧‧‧Infrared absorption zone

43‧‧‧Interval window

311‧‧‧ Main body

40‧‧‧ openings

312‧‧‧Electric pin end

5‧‧‧Second patterned polysilicon layer

313‧‧‧Second auxiliary etching tunnel

51‧‧‧second infrared absorption zone

32‧‧‧Optocrystalline structure area

511‧‧‧Electrical connection

321‧‧‧Optocell unit

52‧‧‧Perforation

4‧‧‧Inline unit

53‧‧‧Auxiliary cavity

Other features and effects of the present invention will be described with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view showing a conventional infrared sensor; FIG. 2 is a cross-sectional view showing a first preferred embodiment of the infrared sensing wafer of the present invention; FIG. 4 is a plan view showing another embodiment of the infrared absorbing region; FIG. 5 is a cross-sectional view showing the infrared ray of the present invention; FIG. A second preferred embodiment of the sensing wafer; and FIG. 6 is a cross-sectional view showing a third preferred embodiment of the infrared sensing wafer of the present invention.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are denoted by the same reference numerals.

Referring to FIG. 2 and FIG. 3, a first preferred embodiment of the infrared sensing chip of the present invention is suitable for detecting infrared rays having a wavelength range of 770 nm to 1 μm, and includes a wafer substrate 2 and a wafer substrate 2 thereon. The patterned polysilicon layer 3 and an interconnect unit 4 on the patterned polysilicon layer 3, and the infrared sensing wafer of the present invention can be sensed particularly for infrared rays having a wavelength of λ.

The wafer substrate 2 is made of a semiconductor material, and includes a top surface 21 and a bottom surface 22 opposite to the top surface 21, and the patterned polysilicon layer 3 is formed on the top surface 21 of the wafer substrate 2.

The patterned polysilicon layer 3 is composed of poly-silicon, and includes an infrared absorbing region 31 and a transistor structure region 32. The transistor structure region 32 cooperates with the wafer substrate 2 to form a plurality of convertible layers. The transistor unit 321 for reading the change in resistance generated by the infrared absorbing region 31, so that only two transistor units 321 are shown in the first preferred embodiment, but it can be easily understood that In the integrated circuit process, the number and form of the required transistors can be produced according to requirements, such as peripheral circuits, capacitors, etc., which are well known to those skilled in the art, and therefore will not be further described herein.

The infrared absorbing region 31 includes a main body portion 311 and two electric pin end portions 312 connected to the main body portion 311, and the main body portion 311 absorbs incident infrared rays to generate a resistance change, and the electric pins are formed by the electric pins. The end portion 312 is electrically connected to the corresponding transistor unit 321 to convert the resistance change through the transistor unit 321 into an electrical signal output. In particular, the infrared absorption region 31 is formed by the same integrated circuit process as the polycrystalline germanium material, and the polysilicon is changed in temperature due to temperature rise after absorption of infrared rays, that is, utilization is utilized. The pyroelectric principle is used to sense infrared rays in the environment; it is worth mentioning that the present invention utilizes the existing steps and raw materials in the integrated circuit process to produce an infrared sensing film layer that must be separately manufactured due to material process limitations. (as described in the prior art, cadmium telluride or vanadium oxide), although the temperature coefficient of resistance (TCR) of polycrystalline germanium is not high compared with cadmium telluride or vanadium oxide, but with the present invention The design of a structure (cavity 410) can be improved to make the infrared sensing wafer of the present invention The sensitivity has been improved, and this part of the structure will be detailed later.

The interconnecting unit 4 is disposed on the wafer substrate 2 and the patterned polysilicon layer 3, and includes a plurality of metal layers 41 in a predetermined electrical connection arrangement pattern and an opening 40 through which infrared rays are incident on the infrared absorption region 31. 40 corresponds to the upper portion of the main body portion 311 formed in the infrared absorption region 31. In addition, for the sake of illustration, in the first preferred embodiment, the two metal layers 41 are taken as an example, and the metal layer 41 closest to the wafer substrate 2 is defined as the first metal layer 41a. The metal layer 41 away from the wafer substrate 2 is a second metal layer 41b. In more detail, the interconnect unit 4 includes a plurality of dielectrically supported dielectric layers 42 in addition to the metal layers 41. And a plurality of vias 43 electrically connected between the different metal layers 41, and the arrangement of the dielectric layers 42 and the vias 43 is a manufacturing step of the integrated circuit process, and is not the technical focus of the present invention. Not to be explained in detail here.

In particular, the first metal layer 41g has a reflective block 411 directly above the main body portion 311 and cooperates with the main body portion 311 to define a cavity 410. The cavity 410 communicates with the outside world to allow infrared energy to enter. In the cavity 410, the distance H1 from the lower surface of the reflective block 411 to the top surface of one of the main body portions 311 of the infrared absorption region 31 is (2n+1)λ/4, and n is a positive integer or zero. λ is a wavelength value of infrared rays; that is, the height of the cavity 410 is an integral multiple of a quarter wavelength of infrared rays to be absorbed, so that infrared rays incident to the cavity 410 form a resonance effect in the cavity 410, Increasing the infrared absorption efficiency of the main body portion 311, thereby improving the sensitivity of detection; in addition, since the reflective block 411 is made of metal (eg, copper), it has a good light reflection effect to make red The outer line is reflected and resonated a plurality of times in the cavity 410 to enhance the peak value.

In addition, the first metal layer 41a further includes an auxiliary etching via 412 surrounding the periphery of the reflective block 411. The auxiliary etching via 412 is used for a chemical etching solution to pass into the interconnecting unit. A portion of the structure of 4 is etched to form the cavity 410, and the cavity 410 is thereby connected to the outside. More specifically, the chemical etchant is introduced by the auxiliary etched via 412 to begin selective downward. Etching to the infrared absorption region 31 composed of polycrystalline silicon and controlling the etching time to form the cavity 410; although a structure similar to the formation of a void below the infrared sensing layer body (such as the configuration of No. 11 in FIG. 1) is conventionally used, The effect of the void is heat insulation, avoiding the temperature generated by the infrared sensing layer body absorbing infrared rays to be too fast, resulting in insufficient sensing sensitivity, and controlling the height of the cavity 410 and resonating the incident wave with the emphasis of the present invention. The structure for enhancing infrared absorption is irrelevant, and the effect claimed by the present invention cannot be achieved, and it is specifically described herein.

Referring to FIG. 4, the main body portion 311 of the infrared absorption region 31 may be formed into a serpentine shape in addition to a rectangular flat shape as shown in FIG. 3, and the electric pin end portions 312 are formed in the serpentine shape. Both ends of the main body portion 311 are illustrated; it is explained that the pattern of the infrared absorption region 31 is determined by design considerations, but the embodiment is of course not limited to the first preferred embodiment.

Referring to FIGS. 2 and 3, when infrared rays are incident from the opening 40 and reach the main body portion 311 of the infrared absorption region 31, portions are directly absorbed by the main body portion 311, and part of the infrared rays are reflected and absorbed a plurality of times, and the portion is absorbed. The infrared ray is lost during the reflection travel, and the infrared ray of the wavelength λ is further resonated by the cavity 410 of the predetermined height distance H1 to increase the temperature change and the resistance change amount of the main body portion 311 of the infrared absorption region 31, thereby improving The sensitivity of the overall sensing. That is to say, although the temperature coefficient of resistance of polycrystalline germanium is lower than the conventional high temperature coefficient of resistance materials, such as cadmium telluride (HgCdTe) or vanadium oxide (V ₂ O ₅ ), the height of the cavity 410 is limited. The incident infrared ray reaches a resonance effect, and the design of the signal transmission loss is reduced by the direct electrical connection of the interconnect unit 4, so that the infrared absorbing region 31 composed of the polycrystalline silicon of the present invention is still produced at a low material cost and low process cost. The required sensing sensitivity can be achieved.

It is emphasized again that since the present invention utilizes a process of a general integrated circuit gate material-polysilicon to simultaneously prepare the infrared absorption region 31, not only the material and the machine equipment are compatible with the general integrated circuit process, therefore, The infrared sensing element and the transistor element which have to be separately manufactured in the past can be integrated into a system single wafer, so that the overall infrared sensing wafer can be made thinner and the market advantage of the product can be improved.

Referring to FIG. 5, a second preferred embodiment of the infrared sensing wafer of the present invention is similar to the first preferred embodiment except that the wafer substrate 2 further includes a body portion located in the infrared absorption region 31. The second resonant cavity 20 is located below the 311, and the infrared absorbing region 31 further has a second auxiliary etched via 313 that communicates with the second resonant cavity 20.

In more detail, the second auxiliary etching via 313 surrounds the periphery of the main body portion 311 and is used for etching a portion of the structure of the wafer substrate 2 by another chemical etching liquid to form the second resonant cavity 20 , and The second resonant cavity is connected to the outside; and after the wafer substrate 2 is etched, the wafer substrate 2 forms an inner annular surface 23 extending from the top surface 21 toward the bottom surface 22, and a connection The base surface 24 of the bottom edge of the inner annular surface 23 is defined by the inner annular surface 23 and the base surface 24 to define the second resonant cavity 20, and the etching time is controlled to cause the bottom surface of the main body portion 311 to the base surface. The distance H2 of 24 is (2n+1) λ/4, and n is a positive integer or zero.

At the same time, the second auxiliary etching hole 313 is also used to partially enter the infrared ray into the second resonant cavity 20, and the second resonant cavity 20 of the height H2 is used to reflect and travel at the second resonant cavity 20. Resonance is generated for the infrared ray of λ, and the absorption effect of the main body portion 311 of the infrared absorption region 31 on incident infrared rays is further improved, and the sensing sensitivity is improved.

Referring to FIG. 6, a third preferred embodiment of the infrared sensing wafer of the present invention is similar to the first preferred embodiment, except that the third preferred embodiment further includes a spacer formed on the patterned polysilicon layer. a second patterned polysilicon layer 5 on 3, and the second patterned polysilicon layer 5 includes a second infrared absorption region 51 above the infrared absorption region 31 of the patterned polysilicon layer 3, and at least one through the second The perforations 52 of the infrared absorption region 51. It is additionally noted that the second patterned polysilicon layer 5 is performed by a 2P (2 poly) process in an integrated circuit (generally an IC design for a capacitor), and therefore, the overall fabrication is still an integrated body. The circuit process is mainly, and no additional material equipment is needed, so the effect of integrating the infrared sensing element and the circuit component of the invention into a system single chip can still be achieved.

And the second infrared absorption of the second patterned polysilicon layer 5 The upper surface of the region 51 cooperates with the reflective block 411 of the first metal layer 41a to define a cavity 410' having a height distance H3, and H3 controls the value to be (2n+1) λ/4, and n is positive. An integer or zero, λ is the incident infrared wavelength, so that infrared rays incident on the cavity 410' resonate in the cavity 410' to enhance the infrared absorption rate of the second infrared absorption region 51; meanwhile, the second infrared The absorbing region 51 has two electrical connecting ends 511 respectively located on the two sides, and the electrical connection of the electrical connecting ends 511 through the interconnecting unit 4 can transmit the resistance change of the second infrared absorbing region 51 due to absorption of infrared rays to the phase Corresponding transistor unit 321 , in more detail, in the third preferred embodiment, the second infrared absorbing region 51 and the infrared absorbing layer 31 are electrically connected in parallel by the interconnect unit 4 to improve Sensing sensitivity.

Preferably, the second infrared absorbing region 51 and the main body portion 311 of the patterned polysilicon layer 3 are also etched by the through holes 52 to form an auxiliary resonant cavity 53. The auxiliary resonant cavity 53 is connected to the through hole 52. And the distance L between the second infrared absorption region 51 and the main body portion 311 of the patterned polysilicon layer 3 is also (2n+1)λ/4, and n is a positive integer or zero, which can cause incident to the auxiliary. The infrared ray of the resonant cavity 53 generates a resonance effect, and at the same time, the absorption effect of the second infrared ray absorbing region 51 and the main body portion 311 on infrared rays is enhanced, thereby increasing the sensing sensitivity of the entire device to infrared rays.

In summary, the infrared sensing wafer of the present invention is based on the principle of operation of the pyroelectric effect, and is integrated with the transistor unit 321 into a single wafer. The polycrystalline germanium selected by the integrated circuit process of the general germanium wafer is used as the infrared light. The absorbed material is further matched with the cavity 410, 410', the second resonant cavity 20 or the auxiliary whose height is limited to (2n+1)λ/4, and n is a positive integer or zero The resonant cavity 53 causes the infrared rays of the wavelength λ incident into the cavity 410, 410', the second resonant cavity 20 and the auxiliary resonant cavity 53 to resonate during the reflection traveling, so that the main body portion 311 and the second infrared ray The absorption effect of the absorption region 51 on the infrared ray is improved, thereby improving the detection sensitivity; at the same time, the reflection block 411 formed by the fabrication of the metal layer 41 can cause most of the incident infrared rays due to the high reflection property of the metal material to the light wave. The reflection is directed to the second infrared absorbing region 51 to further improve the absorption efficiency of the infrared ray; therefore, the infrared ray sensing wafer of the invention not only has a low process cost, but also can be integrated with the transistor to reduce the volume of the single wafer process and improve the loss of the electrical conduction path. The sensing sensitivity is good, and the object of the present invention can be achieved.

The above is only the preferred embodiment of the present invention, and the scope of the present invention is not limited thereto, that is, the simple equivalent changes and modifications made by the patent application scope and patent specification content of the present invention, All remain within the scope of the invention patent.

2‧‧‧ Wafer substrate

41‧‧‧metal layer

21‧‧‧ top surface

41a‧‧‧First metal layer

22‧‧‧ bottom

41b‧‧‧Second metal layer

3‧‧‧ patterned polycrystalline layer

411‧‧‧Reflecting block

31‧‧‧Infrared absorption zone

412‧‧‧Auxiliary etching tunnel

32‧‧‧Optocrystalline structure area

410‧‧‧ cavity

321‧‧‧Optocell unit

42‧‧‧Dielectric layer

4‧‧‧Inline unit

43‧‧‧Interval window

40‧‧‧ openings

H1‧‧‧ distance

Claims (5)

An infrared sensing chip for detecting an infrared ray having a wavelength of λ, the infrared sensing wafer comprising: a wafer substrate, comprising a semiconductor material, comprising a top surface, and a bottom surface opposite to the top surface; a patterned polysilicon layer on a top surface of the wafer substrate defines a transistor structure region and an infrared absorption region, and the transistor structure region cooperates with the wafer substrate to form a plurality of transistor units capable of converting electrical signals The infrared absorbing region includes a main body portion and two electric pin ends connected to the main body portion, and the main body portion absorbs incident infrared rays to generate a resistance change, and corresponds to the end portions of the electric pins. Electrical connection of the transistor unit causes the resistance change to be converted into an electrical signal output through the transistor unit; and an interconnect unit located on the wafer substrate and the patterned polysilicon layer, including a plurality of layers in a predetermined electrical connection configuration a patterned metal layer and an opening for the infrared ray to be incident on the infrared absorbing region, wherein a metal layer has a reflective block directly above the main body portion, The shot block cooperates with the main body portion to define a cavity that communicates with the outside to allow infrared energy to enter the cavity, and a lower surface of the reflective block to a top surface of one of the main body portions of the infrared absorption region The distance is (2n+1)λ/4, and n is a positive integer or zero. The infrared sensing wafer of claim 1, wherein the wafer substrate further comprises an inner annular surface extending from the top surface toward the bottom surface, and a base surface connecting the bottom edge of the inner annular surface, and the inner ring Face and the base surface Forming a second resonant cavity formed in the wafer substrate, and the second resonant cavity is located under the main body portion of the patterned polysilicon layer and communicates with the outside to allow infrared energy to enter the second resonant cavity, and One of the main body portions is opposite to the bottom surface of the top surface to the base surface by a distance of (2n+1)λ/4, and n is a positive integer or zero. The infrared sensing wafer of claim 2, wherein the metal layer having the reflective block further comprises an auxiliary etching via surrounding the reflective block, the auxiliary etching via for supplying a chemical etching solution A portion of the structure of the interconnect unit is etched to form the cavity, and the cavity is thereby connected to the outside. The infrared sensing wafer of claim 3, wherein the infrared absorption region of the patterned polysilicon layer further has a second auxiliary etching via, the second auxiliary etching via surrounding the periphery of the body portion for providing another A chemical etching solution passes through a portion of the structure of the wafer substrate to form the second resonant cavity and allows the second resonant cavity to communicate with the outside. An infrared sensing chip for detecting an infrared ray having a wavelength of λ, the infrared sensing wafer comprising: a wafer substrate composed of a semiconductor material; and a first patterned polysilicon layer on the surface of the wafer substrate, defined a transistor structure region and a first infrared absorption region, the transistor structure region cooperates with the wafer substrate to form a plurality of convertible electrical signal transistor units, the first infrared absorption region includes a main body portion and two Connecting the main body portion and separating the end portions of the electric pins, the main body portion is absorbed The incident infrared ray generates a resistance change, and is electrically connected to the corresponding transistor unit via the ends of the electrical pins to cause the resistance change to be converted into an electrical signal output through the transistor unit; a second patterned polysilicon a layer, the spacer is formed on the first patterned polysilicon layer, and includes a second infrared absorption region above the first infrared absorption region and at least one through hole extending through the second infrared absorption region, and a first The main body portion of the infrared absorption region cooperates with the second infrared absorption region to define an auxiliary resonant cavity, and the auxiliary resonant cavity communicates with the through hole and the distance from the top surface of the main body portion to the bottom surface of the second infrared absorption region is (2n+ 1) λ / 4, and n is a positive integer or zero, the second infrared absorption region absorbs infrared rays to generate a resistance change and is electrically connected to the corresponding transistor unit to convert the resistance change through the transistor unit to An electrical signal output, and the perforation causes incident infrared rays to pass through to reach a main body portion of the first infrared absorption region, and the auxiliary resonant cavity is incident on the auxiliary resonant cavity The external line generates a resonance phenomenon; and an interconnecting unit is disposed on the surface of the wafer substrate, and includes a plurality of metal layers formed into a predetermined electrical connection arrangement pattern, and an opening for injecting infrared rays into the second infrared absorption region, wherein the metal The layer has a reflective block directly above the second infrared absorbing region, and the reflective block cooperates with the second infrared absorbing region to define a cavity, and the cavity communicates with the opening to allow infrared energy to enter the cavity And the distance from the lower surface of the reflective block to the upper surface of the second infrared absorption region is (2n+1)λ/4, and n is a positive integer or zero; wherein the second infrared absorption region has two separations Set up electrical connection Connecting the electrical connection terminals to the interconnecting unit to transmit the resistance change of the second infrared absorbing region due to absorption of infrared rays to the corresponding transistor unit, and the second infrared absorbing region and the The body portion is electrically connected in parallel by the interconnect unit.