TWI293112B - An underwater acoustic micro-sensor - Google Patents

Description

1293112 IX. Description of the invention: [Technical field to which the invention belongs] The present invention relates to an apparatus for an underwater acoustic micro-sensor, which is fabricated using a surface processing technique of a micro-electromechanical process. The sensor ^ senses the structure of the film when receiving sound waves in a specific frequency range close to the natural frequency of the structure, the sensor wheel signal has a high signal-to-noise ratio characteristic, thereby receiving the signal transmitted by the underwater sound wave content. [Prior Art] The research department of MEMS combines the traditional micro-sensor and actuator system developed by the knowledge and semi-guided technology of electronics, motor, machine, biomedical and control. For applications in various fields, the miniaturization of the sensing system, and the right, the point g 敫 (four) eight have a mixed load, reduce the occupied area, reduce the second _ 抽 抽 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 On the sensor, not only can make ❹ 赖 _ _ small money. The pair can be improved, and the secret fee is taken, the wealth (four), the Bu... A sci-fi month is also lower; in addition, and can be combined with semiconductor technology Manufactured-array-type sensors. Although the current industry has developed a multi-micro-electromechanical system, its application range is quite wide, and it has a wide range of applications. The development of sensors is quite lacking. In view of this, the inventor of this case has been exhausted, carefully researched, and researched on the open-air device, using the well-known pressure sensor as the basis of the sound of the range technology and underwater acoustic technology. Sound /, 胄 combined with micro-electromechanical despicable city sensor. This underwater measurement

CKU-P060054-TW 6 1293112 The combination of technology, I believe that will bring the underwater measurement technology breakthrough [invention content] The main purpose of this book is to provide a combination of micro-electromechanical process crying, ft processing technology and underwater acoustics The underwater sound of the technology is micro-sensing sound micro-sensing i. Low cost, low accuracy, low energy consumption

For the purpose of the above, the sensor structure of the present invention is as shown in FIG. 1, and the following structure: a lower structure: a set of piezoresistive, a group conductor circuit, an insulation (four) ^ sensing film, and a waterproof film. Among them, you / [resistance, and] is made of polycrystalline stone eve, and ion implanted side ions, = inch appearance. The piezoresistive group is a group of four piezoresistors, which: w two in the thin county structure apologizes the sensing end of the piezoresistive ::= change and change - and two are not set on the film structure:

The wire circuit group is made of gold as a wire material and connected to four piezoresistive group bridge circuits. The electricity contains four (4) contacts, which are divided into two:: ―, which is the input terminal and the ground terminal of the external _, and the other pair is the output terminal of the sensor voltage signal. = Insulation material is made of nitrogen cut, which is located on the single (4) substrate of piezoresistive and conductive materials to avoid short circuit. The material is used to directly use the single-rotation wafer as the substrate. The front surface is first formed by the film-shaped groove (4), and then the crystal is further

CKU-P060054-TW 1293112 = Kawasaki version engraved 槿, (4) seven structures. The outer surface of the film is a slender type; the Γ Γ mode is simplistic, and the width of the left and right sides of the film is smaller than that of the U-shaped groove of the U tooth to reduce the structural stiffness and the self-D vibration frequency. U The waterproof film is deposited on the outer layer of the sensor, wherein the waterproof film is a layer of Parylene to prevent moisture from entering the sensor to conform to the underwater operating environment.

When designing the reticle, the limitation of the wafer space and the power of the sensor should be considered. Therefore, when designing the sensor on the wafer, except for a single sensor placed in a single test wafer, as shown in Figure 2 As shown, two and four sensors are simultaneously configured on a single test wafer. In addition to increasing the number of sensors and reducing unit cost, test wafers with four sensors design four sensing films of different lengths, giving them different resonant frequencies to enhance the performance of the sensing wafer. [Embodiment] In order to facilitate the examination committee to further understand, understand and understand the structure, use and characteristics of the present invention, the inventors cite several preferred embodiments, with detailed drawings The description is as follows: The main manufacturing method and structure of the present invention are described in detail in FIG. 3 and FIG. The following is a description of the process flow chart of the micro sensor of the present invention, wherein the sensing

CKU-P060054-TW

Claims (1)

1293112 y year & month alpha repair (more) is replacing page, patent application garden: ------- 1 · A sound micro sensor for k people, underwater soil, its The structure includes ·, and [resistance, which is made of polycrystalline germanium, and is ion-implanted to make [resistance characteristics appear, and four voltage resistances are used as a group, and the V-line circuit connects the four piezoresistives. Forming the Wheatstone electric f7 road, the circuit contains four contacts; the insulating material is located under the piezoresistive and metal wires to block the conductive single crystal germanium substrate; and the sensing thin m' is used as The single crystal germanium wafer of the substrate is a material whose shape is an elongated structure; and a waterproof film is deposited on the outer layer of the sensor. 2. The sensor of claim 1, wherein the pressure has two sensing end-resistances on both sides of the film structure, the resistance value of which changes with the deformation of the thin structure; Piezoresistors that are not fixed in the structure of the film are fixed. 3. The sensor of claim 1, wherein the conduction=connecting four piezoresistives constitutes a Wheatstone bridge circuit, the circuit comprising four contacts, which are divided into two pairs, one pair being added The input terminal of the voltage and the ground terminal, and the other pair is the output terminal of the sensor voltage signal. 0 CKU-P060054-TW 15 1293112 year f month (7 days repair i) is replacing page 4 · as patent application scope 1 ^ The sensor of the above description, wherein the sensing film structure is of an elongated shape, the width of the left and right sides is narrower, and the outer film groove is etched around the periphery. 5. The sensor of claim 1, wherein the pressure is J1 and is implanted with a sputum ion. 6. The sensor of claim 1, wherein the wire circuit is made of gold. 7. The sensor of claim 1, wherein the insulating material is a tantalum nitride compound. 8. The sensor of claim 1, wherein the water-repellent film is made of a parylene material. 9. The sensor of claim 2, wherein the piezoresistive is etched using an inductively coupled plasma ion etching system (ICP). 1. The sensor of claim 1, wherein the film is formed by a back etching method to form a film structure of a suitable thickness to simplify the vibration mode. C 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 The opened I-worm hole is cut with a convenient wafer. 12. The sensor of claim 1, wherein the back etching method is to cover the dicing line with a photoresist when etching to a half thickness of the sensing film to avoid causing the sensing film to be The film is not strong enough to break. 13·—A kind of acoustic micro-sensor used in underwater environment, the structure of which includes: - group piezoresistive resistance is a group of four piezoresistors; - group conductor circuit is connected with four piezoresistive components to form Whisttown The bridge circuit; the insulating material is located under the piezoresistive and the metal wire to block the conductive single crystal germanium substrate, and the sensing film is directly used as a substrate of the single crystal germanium wafer as a material, and the shape thereof is a slender structure; and a waterproof film deposited on the outer layer of the sensor; wherein the sensing film is precisely etched to the thickness of the crucible by back etching, the thickness of the sensing film is close to natural vibration When the sound wave of the frequency range is used, the signal of the high signal ratio can be output. CKU-P060054-TW 17 1293112 曰修 (more) 正^ 14·A sound change method that can be applied to underwater environments, the steps of which include: the deposition of the paste maker is nitrided on a single crystal dream base; Depositing polycrystalline germanium on the tantalum nitride layer to block the material; arranging and implanting ions to form the polycrystalline tantalum film 'to form the shape of the piezoresistive layer · depositing gold and surging a gold wire on the polycrystalline second film; Piezoresistive composition of the Wheatstone bridge circuit; removal of excess nitrite by reactive ion (IV) (RIE); etching of the single-crystal 矽 front film outer groove; , forming a film structure of appropriate thickness in a back_mode And a deposited-Parylene waterproof layer. 15. The manufacturing method according to claim 14, wherein before the etching step, a step of grinding the surface of the film is further included to avoid the weed phenomenon caused by the deep etching behind and the curvature of the underside of the etching. is too big. CKU-P060054-TW 18 1293112 Sw Sweep Frequency LIE-8- n nc n 1 ncr o -- spn:ljQ.£y UJrM:p<D:dsx.9M0d .0k5,0k 10,0k 15.0k 20,0k 25.0k frequency Pfoto I ' « 35.0k 40.0k 45.0k six Iropency(lfe) Volume seven 23' CKU-P060054-TW