TWI513027B - Flexible light sensor - Google Patents

Description

Flexible light sensor

The present invention relates to a flexible light sensor for sensing blood oxygen saturation in blood, and more particularly to a flexible photosensor formed by a semiconductor process, which mainly has flexible characteristics. It can be attached to the skin of the non-flat surface of the human body, or to the auxiliary device used by the human body. The flexible photosensor uses the principle that different red blood cells can absorb different spectra to perform spectral sensing.

Generally, in the development of blood oxygen sensing arrays, changes in blood oxygen concentration are important indicators for detecting sleep-disordered breathing, and blood oxygen sensing is used to detect changes in blood oxygen concentration in sublingual blood vessels. Hemoglobin produces different light absorbing properties in the presence of oxygen and no oxygen. Oxygenated hemoglobin and protohemoglobin have a spectral difference between 600nm and 1000nm under visible red light. The difference in absorption spectral characteristics is the largest, so the use of infrared spectroscopy can be a simple and reliable method for measuring the oxygen content of blood in tissues. method.

The traditional instrument for detecting blood oxygen is a pulse oximeter, which is a non-invasive sensing device that can be estimated by the user's current pulse by simply pinching it on the finger. Oxygen saturation (SpO2). The red blood cells carrying oxygen can absorb more infrared light, the spectrum of infrared light is between 850nm and 1000nm, and the red blood cells without oxygen are more red light, and the spectrum of red light is between 600nm and 750nm. Therefore, blood oxygen saturation is analyzed by the principle that different red blood cells absorb different spectra. Therefore, if the blood oxygen concentration SpO2 is in the sleep state At 88%, it can indicate that sleep disordered breathing occurs.

In the prior art, Soren Dahl Petersen provides an A flexible infrared sensor for tissue oximetry, in which the sensor detects the oxygen saturation in the brain tissue through the infrared spectrum, and the sensor itself is a plurality of fluorescent detectors. The integrated circuit is fabricated by a standard semiconductor process, and bismuth is combined with polydimethyl siloxane and polyimide. It is therefore flexible and can withstand bending.

However, the polydimethyl methoxy olefin described in the art has the entire sensor packaged therein, and the sensors are also filled with polydimethyl siloxane, so that when bent, the sensor There is no extra space between them for bending, resulting in a smaller bendable angle.

The object of the present invention is to provide a flexible photosensor, which is mainly a photosensor formed by a semiconductor process, and has a flexible base layer formed by a polymer film, and has a flexible light sensation. The detector comprises a plurality of light sensing devices, and the light sensing devices have a space between them, whereby the flexible light sensor can be used to coat or attach the flexible light sensor to any non-flat table. On the surface, and between the light sensing devices, there is a space for spacing, so that the bending angle of the flexible light sensor is larger.

The flexible photosensor of the present invention is formed by a semiconductor process, comprising: a base layer, which is a polymer material, has flexibility, includes a through hole; and a plurality of light sensing devices are separated by a deposition process a bottom layer disposed on the base layer of the base layer; a connecting layer deposited on the lower surface and the side surface of the light sensing device and the lower surface of the base layer in the space, and forming a continuous surface; and the light source module disposed on the bottom The hole is configured to emit a plurality of light sources, wherein a gap between any two of the consecutive light sensing devices after the deposition of the connection layer is provided.

As described above, in an embodiment, wherein the base layer further comprises a circuit via a deposition etching process electrically connecting the photo sensor devices.

As described above, in an embodiment, the light source module is a light emitting diode.

As described above, in an embodiment, the spectra of the light sources simultaneously include red light of 660 nm and infrared light of 940 nm.

As described above, in an embodiment, the base layer and the connecting layer are transparent polymer materials.

As described above, in one embodiment, wherein the base layer and the tie layer are parylene.

As described above, in one embodiment, the connecting layer is further a parylene of a conformal coating material.

As described above, in an embodiment, the light sensing devices are photodiodes.

The invention further provides a method for manufacturing a flexible photosensor, the method comprising: providing a germanium substrate, forming a P+ germanium by a high temperature annealing process, and then using the phosphorus oxychloride as a carrier, followed by high temperature annealing to form N+矽Then, the para-xylene is deposited on the upper surface of the germanium substrate of the germanium substrate, and then the micro-etching process is used to form a circuit. The circuit is electrically connected to the P+矽 of the germanium substrate, and then the germanium substrate is etched by deep etching to form a plurality of light sensing. a device, and the light sensing devices are spaced apart from each other, and then the via holes are etched by deep etching; then the side surfaces and the lower surface of the light sensing devices and portions of the light sensing devices are not provided with the light sensing devices Depositing a parylene layer on the lower surface of the base layer of the base layer to form a connecting layer, the connecting layer is a continuous surface, and the space between the light sensing devices forms a space after depositing the connecting layer, and a light source is disposed at the through hole Module.

The invention utilizes two different light source modules with different spectra of 660 nm and 940 nm to emit red light and infrared light to absorb the oxygen-free and oxygen-carrying red blood cells, and then measure the reverse color light reflected by different red blood cells by the light diode, and measure The oxygen content of red blood cells. In addition, the present invention utilizes a flexible polymer material as a flexible photosensor formed by the base layer, so that it can be attached to any non-flat surface, and the conventional rigid board PCB can not be attached to any non-flat surface. Surface demand. In addition, the flexible photosensor of the present invention uses a good conformal coating of parylene to separate the gaps between the light sensing devices, and deposits the connecting layer in the space by a CVD process. The lower surface of the base layer and each light The side surface and the lower surface of the sensing device are formed into a continuous surface, and a space between any two consecutive photosensitive sensing devices after the deposition of the connecting layer is provided, so that the flexible effect of the flexible photo sensor is further improved. The bending angle is larger.

10‧‧‧矽 substrate

11‧‧‧P ⁺矽

12‧‧‧N ⁺矽

15‧‧‧矽Upper surface of the substrate

16‧‧‧矽Under the surface of the substrate

20‧‧‧ basal layer

21‧‧‧ Circuitry

30‧‧‧ Groove

31‧‧‧through hole

40‧‧‧ nitride

50‧‧‧2 cerium oxide

60‧‧‧Light sensing device

61‧‧‧ side surface

62‧‧‧ lower surface

63‧‧‧The lower surface of the basal layer

70‧‧‧Connection layer

80‧‧‧Light source module

90‧‧‧ interval

91‧‧‧Interval space

95‧‧‧Light source

96‧‧‧ Reflected light

1 is a cross-sectional view of a P-type germanium substrate in a method of fabricating a flexible photosensor according to the present invention.

2 is a cross-sectional view showing the formation of P ⁺矽 and N ⁺中 in a method of manufacturing a flexible photosensor according to the present invention.

3 is a cross-sectional view of a deposited substrate layer in a method of fabricating a flexible photosensor in accordance with the present invention.

4 is a cross-sectional view of a P-type germanium substrate etched in a method of fabricating a flexible photosensor according to the present invention.

5 is a cross-sectional view showing a light-emitting diode disposed in a hole in a method of manufacturing a flexible photosensor according to the present invention.

Figure 6 is a cross-sectional view of a flexible light sensor in accordance with the present invention when bent.

The above and other objects, features, and advantages of the present invention will become more apparent from the accompanying drawings in the appended claims. 1 and 2, FIG. 1 is a cross-sectional view of a P-type germanium substrate in a method of manufacturing a flexible light sensor according to the present invention, and FIG. 2 is a view showing a method of manufacturing a flexible light sensor according to the present invention. ⁺矽 and N ⁺矽 profiles. First, a ruthenium substrate 10 is provided, wherein the ruthenium substrate 10 is a P-type single crystal ruthenium substrate, followed by deposition of tetraethyl decane (TEOS) as a mask, followed by deposition of a telluride (BSG), followed by a high temperature annealing process. P ⁺矽 11 is formed, followed by phosphorus oxychloride (POCl ₃ ) as a carrier, which is annealed at a high temperature to form N ⁺矽12.

Next, please refer to FIG. 3, which is a cross-sectional view of a deposited substrate layer in a method of fabricating a flexible photosensor according to the present invention. Depositing parylene on the upper surface 15 of the ruthenium substrate 10 of the ruthenium substrate 10 as the base layer 20, and then etching the holes with photoresist and oxygen, depositing gold (Au), and using a photolithography process to gold (Au) is etched into the circuit 21, and the circuit 21 is electrically connected to the ruthenium substrate 10, followed by deposition of parylene, and finally the parylene is etched to form the groove 30, and the groove 30 is later It is etched into a via hole, so that the groove 30 does not overlap with P ⁺矽 11 or N ⁺矽 12 of the ruthenium substrate 10.

Next, tantalum nitride (SiN) 40 is deposited on the lower surface 16 of the tantalum substrate of the tantalum substrate 10, and then ruthenium dioxide (SiO2) 50 is deposited under the tantalum nitride 40.

Next, please refer to FIG. 4. FIG. 4 is a cross-sectional view of a P-type germanium substrate etched in a method of manufacturing a flexible photosensor according to the present invention. Then, the germanium substrate 10 is etched by deep etching to form a plurality of light sensing devices 60, wherein the light sensing device 60 is also a photodiode, and each of the light sensing devices 60 has a space of 90, and then etched back. The through hole 31 is etched corresponding to the groove 30.

Referring to FIG. 5 and FIG. 6 , FIG. 5 is a cross-sectional view of a through-hole light-emitting diode disposed in a method for manufacturing a flexible photosensor according to the present invention, and FIG. 6 is based on FIG. A cross-sectional view of the flexible photosensor of the present invention when bent. Next, the side surface 61 and the lower surface 62 of the sensing device 60 and a portion of the lower surface 63 of the substrate layer on which the light sensing device 60 is not disposed are deposited with a parylene forming connection layer 70, and the formed connection layer 70 is continuous. The surface, the space 90 formed between the respective light sensing devices 60, forms a space 91 after deposition of the connection layer 70.

Next, a light source module 80 is disposed at the through hole 31 to form a flexible photo sensor. The light source module 80 simultaneously emits red light having a spectrum of 660 nm and infrared light of 940 nm.

The present invention forms a flexible photosensor by the above method, and the flexible photosensor of the present invention is formed by a semiconductor process, comprising: a base layer 20, which is a polymer material, and has The flexible portion includes a through hole 31; a plurality of light sensing devices 60 are disposed at intervals on the base layer lower surface 63 of the base layer 20 via a deposition process; and the connection layer 70 is deposited on the lower surface 62 of the light sensing devices 60. And a side surface 61 and a lower surface of the base layer in the space, and forming a continuous surface; and a light source module 80 disposed in the through hole 31 for emitting a plurality of light sources 95, wherein any one after the deposition of the connection layer There is a space 91 between the successive light sensing devices.

As described above, in an embodiment, the base layer 20 further includes a deposition forming circuit 21 via a deposition etching process electrically connected to the photo sensor devices 60.

As described above, in an embodiment, the light source module 80 is a light emitting diode.

As described above, in an embodiment, the spectra of the light sources simultaneously include red light of 660 nm and infrared light of 940 nm.

As described above, in an embodiment, the base layer 20 and the connection layer 70 are transparent polymer materials.

As described above, in one embodiment, the base layer 20 and the tie layer 70 are parylene.

As described above, in one embodiment, the tie layer 70 is further a parylene of a conformal coating material.

As described above, in an embodiment, the light sensing devices 60 are photodiodes.

The invention utilizes two different light source modules with different spectra of 660 nm and 940 nm to emit red light and infrared light to absorb the oxygen-free and oxygen-carrying red blood cells, and then use the light diode to sense the reflected light 96 reflected by different red blood cells, and utilize The spectrum of the reflected light 96 measures the oxygen content of the red blood cells. In addition, the present invention utilizes a flexible polymer material as a flexible photosensor formed by the base layer, so that it can be attached to any non-flat surface, and the conventional rigid board PCB can not be attached to any non-flat surface. Surface demand. In addition, the flexible photosensor of the present invention etches the light sensing devices, and then uses a good conformal coating of parylene to deposit the connecting layer on the unset light by using a CVD process. The lower surface of the base layer of the sensing device and the lower surface and the side surface of each of the light sensing devices, and a continuous surface is formed, so that the light sensing device can be more firmly connected to the base layer, and any two after the deposition of the connecting layer Continuous light sensing There is a space between the devices 91, which makes the flexible light sensor more flexible and has a larger bending angle.

In the above, it is merely described that the present invention is an embodiment or an embodiment of the technical means for solving the problem, and is not intended to limit the scope of implementation of the present invention. That is, the equivalent changes and modifications made in accordance with the scope of the patent application of the present invention or the scope of the invention are covered by the scope of the invention.

20‧‧‧ basal layer

21‧‧‧ Circuitry

31‧‧‧through hole

60‧‧‧Light sensing device

61‧‧‧ side surface

62‧‧‧ lower surface

63‧‧‧The lower surface of the basal layer

70‧‧‧Connection layer

80‧‧‧Light source module

91‧‧‧Interval space

95‧‧‧Light source

96‧‧‧ Reflected light

Claims (8)

A flexible photosensor formed by a semiconductor process, comprising: a substrate layer, which is a polymer material, has flexibility, includes a through hole; and a plurality of light sensing devices are processed through a deposition process Between the lower surface of a base layer of the base layer; a connecting layer deposited on the lower surface and the side surface of the light sensing device and the lower surface of the base layer in the space, and forming a continuous surface; a light source module disposed in the through hole for emitting a plurality of light sources, wherein any two of the consecutive light sensing devices after depositing the connecting layer have a space between the light sources It also includes red light at 660 nm and infrared light at 940 nm. The flexible photosensor of claim 1, wherein the substrate layer further comprises a circuit formed by a deposition etching process electrically connected to the photo sensor devices. The flexible light sensor of claim 1, wherein the light source module is a light emitting diode. The flexible photosensor of claim 1, wherein the base layer and the connecting layer are transparent polymer materials. The flexible photosensor of claim 1, wherein the base layer and the connecting layer are parylene. A flexible photosensor according to claim 4, wherein the connecting layer is further a parylene of a conformal coating material. The flexible light sensor of claim 1, wherein the light sensing devices are light diodes. A method for manufacturing a flexible photosensor, the method comprising: providing a germanium substrate, forming a P ⁺ germanium by a high temperature annealing process, and then using phosphorus oxychloride as a carrier, followed by high temperature annealing to form an N ⁺矽Depositing parylene on a top surface of a substrate of the germanium substrate, and forming a circuit by using a photolithography process, the circuit electrically connecting the P ⁺ germanium of the germanium substrate, etching the germanium substrate by deep etching, Forming a plurality of light sensing devices, and having a space between the light sensing devices, and then etching a through hole by using deep etching, the side surface and the lower surface and portions of the light sensing devices are not disposed Depositing a parylene layer on a lower surface of a base layer of the base layer of the light sensing device to form a connecting layer, the connecting layer is a continuous surface, and the interval between the light sensing devices is connected to the connecting layer Then, a space is formed, and a light source module is disposed at the through hole. The light source module is configured to emit a plurality of light sources, and the spectrum of the light sources includes red light of 660 nm and infrared light of 940 nm.