A flat quadrant laser detector assembly and its preparation method

Abstract

The present invention belongs to the field of semiconductor photodetector technology and discloses a flat quadrant laser detector assembly and a method for manufacturing the same. The detector assembly includes a photosensitive chip, an amplifier circuit, and a device housing. The photosensitive chip and amplifier circuit within the detector assembly are arranged in a planar layout. The photosensitive chip is a quadrant photodiode, which converts received laser signals into pulsed current signals. The amplifier circuit utilizes a monolithic, hollow structure with a circular outer and inner circle, or a circular outer and inner square structure. It is composed of a transistor core, an amplifier chip, and resistors, integrated onto a circuit substrate via double-sided surface mounting. The amplifier circuit converts the multi-channel pulsed current signals output by the photosensitive chip into pulsed voltage signals and amplifies and shapes them for output. The device housing comprises a tube socket containing a tube socket base and pins, and a tube cap containing a tube cap base and a light window. The present invention has the advantages of compact structure, simple process, high overload resistance, low cost, and high reliability.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductor photoelectric detectors and relates to a flat quadrant laser detector component and a preparation method thereof. Background Art

[0002] Photoelectric detection systems used in laser tracking, laser positioning, and free-space laser communications often utilize quadrant-structured laser detector assemblies. These systems calculate and determine target position information based on the magnitude and orientation of the optical axis offset. In practical applications, quadrant laser detector assemblies are installed at the front end of laser systems to receive laser echo signals indicating the target's position. Quadrant laser detector assemblies, due to their compact size, high integration, fast response speed, and excellent resistance to photoelectric interference, are particularly well-suited for the development of high-precision, real-time tracking and positioning systems.

[0003] The photosensitive chip and amplifier circuit in the traditional quadrant laser detector assembly (application publication number: CN108662979A) are mostly arranged in a three-dimensional manner, that is, the photosensitive chip is mounted on the top surface of the "convex" platform of the tube base, and four separate amplifier circuits are mounted on the four sides of the "convex" platform of the tube base respectively. The amplifier circuits are connected by three-dimensional welding. However, the three-dimensional layout has the following shortcomings: (1) The longitudinal dimension of the detector assembly is usually greater than 15 mm, which seriously restricts the application of such devices in systems with compact longitudinal dimensions; (2) The amplifier circuit is mounted on the side of the "convex" platform of the tube base, so that the amplifier circuit can only adopt a single-sided design layout, which affects the redundancy of the amplifier circuit design and increases the design difficulty; (3) The amplifier circuit adopts four separate mountings and is interconnected by three-dimensional welding, which increases the complexity of the detector assembly process and reduces reliability.

[0004] With the continuous development of laser tracking, laser positioning and other systems, higher requirements are placed on the miniaturization and high reliability of quadrant laser detector assemblies, especially the longitudinal dimensions. In response to the problems existing in the above-mentioned traditional quadrant laser detector assemblies, the present invention proposes a flat quadrant laser detector assembly and a preparation method thereof. Summary of the Invention

[0005] (1) Purpose of the invention

[0006] The purpose of the present invention is to address the deficiencies in the prior art and actual needs, and to propose a flat quadrant laser detector assembly in which a photosensitive chip and an amplifier circuit are arranged in a planar manner, and a preparation method thereof.

[0007] (2) Technical solution

[0008] In order to solve the above technical problems, the present invention provides a flat quadrant laser detector assembly, which includes: a photosensitive chip 1, an amplifier circuit 3 and a device housing; the photosensitive chip 1 and the amplifier circuit 3 are both arranged in the device housing, the amplifier circuit 3 is a hollow structure with a central opening, the photosensitive chip 1 is located at the central opening of the amplifier circuit 3, and the top surface of the photosensitive chip 1 and the amplifier circuit 3 are coplanar, the photosensitive chip 1 receives the laser signal and converts it into a pulse current signal, the amplifier circuit 3 receives the multi-channel pulse current signal output by the photosensitive chip 1 and converts it into a pulse voltage signal, and outputs it after amplification and shaping.

[0009] The photosensitive chip 1 is fixed to the conductive tape substrate 2 by means of a conductive adhesive; and the conductive tape substrate 2 is installed and fixed in the device housing by means of an insulating adhesive.

[0010] The photosensitive chip 1 is a quadrant photodiode, and the amplifier circuit 3 is a single-chip hollow structure with an outer circle and an inner circle or an outer circle and an inner square. The amplifier circuit 3 is formed by integrating a transistor core, an amplifier chip and a resistor element on a circuit substrate through double-sided surface mounting.

[0011] The amplifier circuit 3 is further provided with welding holes 4 , which are connected one-to-one with the socket pins 6 provided on the device housing, so as to realize the connection between the amplifier circuit 3 and the signal output electrical appliance through the socket pins 6 .

[0012] The device housing includes a tube base 7 and a tube cap 13 . The amplifier circuit 3 with the photosensitive chip 1 is arranged on the tube base 7 . The tube cap 13 is installed on the tube base 7 and covers the amplifier circuit 3 .

[0013] Among them, the tube seat 7 includes a tube seat base 5 and a tube seat pin 6. The main body of the tube seat base 5 is a circular plate, with a raised circular table II9 in the center of the main body, a raised annular table I8 on the outer periphery of the main body, and a circular concave surface 10 provided on the top of the table II9; the top of the table I8 and the table II9 are coplanar, used to support the installation of the amplifier circuit 3, and the height of the table I8 and the table II9 is ​​based on the space required for the layout of the electronic components on the back of the amplifier circuit 3; the concave surface 10 is used to position and install the conductive tape substrate 2 containing the photosensitive chip 1, the depth of the concave surface 10 is consistent with the thickness of the conductive tape substrate 2, the diameter of the concave surface 10 is larger than the diameter of the conductive tape substrate 2, and the conductive tape substrate 2 and the concave surface 10 are gap-fitted.

[0014] The tube base pin 6 is made of glass insulating material and is sintered with the metal base of the tube base 7 to achieve electrical connection.

[0015] Among them, the tube cap 13 includes a tube cap base 11 and a light window 12 opened in the center of the tube cap base 11. The tube cap base 11 and the light window 12 are formed into a device shell tube cap 13 by welding or brazing; a ring-shaped inclined buffer structure 14 is provided on the top of the tube cap base 11, and the inclined buffer structure 14 is inclined outward and downward to enhance the high overload resistance of the tube cap base 11; the light window 12 is used for the incidence of laser signals.

[0016] The tube base 7 and the tube cap 13 are sealed by laser welding, parallel welding or energy storage welding, and are used to hermetically seal the photosensitive chip and the amplifier circuit with the outside world.

[0017] The present invention also provides a method for preparing a flat quadrant laser detector assembly, the process of which is as follows: a photosensitive chip 1 is fixed to a conductive tape substrate 2 by a conductive adhesive; the conductive tape substrate 2 is installed and fixed on a concave surface 10 structure of a tube seat base 5 by an insulating adhesive, and the two meet the concentricity requirements; the amplifier circuit 3 is installed and fixed on the table I8 and table II9 of the tube seat base 5 by an insulating adhesive, and the welding holes 4 correspond one-to-one to the tube seat pins 6; the electrodes of each quadrant of the photosensitive chip 1 and the corresponding ports of the amplifier circuit 3 are connected through transfer leads at the solder joints of the conductive tape substrate 2, and the ports of the amplifier circuit 3 are connected to the corresponding tube seat pins 6 through the welding holes 4; the tube cap base 11 and the light window 12 are formed into a device shell tube cap 13 by melting or brazing, meeting the airtightness requirements; the tube seat 7 and the tube cap 13 are sealed by laser sealing, parallel sealing or energy storage sealing, meeting the airtightness requirements.

[0018] (3) Beneficial effects

[0019] The flat quadrant laser detector assembly and its preparation method provided by the above technical solution have the following beneficial effects:

[0020] (1) The photosensitive chip and amplifying circuit inside the detector assembly of the present invention adopt a planar layout. Compared with the traditional three-dimensional layout, the longitudinal size of the device can be reduced by more than 50%, further expanding the use of such devices in compact laser tracking and laser positioning systems, especially systems with strict requirements on longitudinal size.

[0021] (2) The amplifier circuit used in the present invention adopts a single-chip outer circle and inner circle (or outer circle and inner square) hollow structure. Compared with the four-piece separate amplifier circuit of the traditional quadrant detector assembly, ① the cost of the single-piece structure amplifier circuit can be reduced by more than 30%; ② the amplifier circuit can be designed with a double-sided layout, which improves the design redundancy and reduces the design difficulty; ③ the mounting process is simple and can be completed with only one mounting; ④ in the detector assembly process, there is no need for a three-dimensional welding process between the four separate amplifier circuits, and the number of lead welding is reduced by more than 60%, thereby improving product reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the laser detector assembly before assembly.

[0023] Figure 2 Schematic diagram of the laser detector assembly being assembled.

[0024] Figure 3 Schematic diagram of the cross-section of the laser detector assembly after assembly.

[0025] In the figure: 1 photosensitive chip, 2 conductive substrate, 3 amplifier circuit, 4 welding hole, 5 tube base, 6 tube base pin, 7 tube base, 8 table I, 9 table II, 10 concave surface, 11 tube cap base, 12 light window, 13 tube cap, 14 tilted buffer structure. DETAILED DESCRIPTION

[0026] In order to make the purpose, content and advantages of the present invention more clear, the specific implementation methods of the present invention are further described in detail below with reference to the accompanying drawings and examples.

[0027] See Figures 1 to 3 As shown, the flat quadrant laser detector assembly provided by the present invention includes a photosensitive chip 1, an amplifier circuit 3 and a device housing; the photosensitive chip 1 and the amplifier circuit 3 are both arranged in the device housing, the amplifier circuit 3 is a hollow structure with a central opening, the photosensitive chip 1 is located at the central opening of the amplifier circuit 3, and the top surface of the photosensitive chip 1 and the amplifier circuit 3 are coplanar. The photosensitive chip 1 receives the laser signal and converts it into a pulse current signal. The amplifier circuit 3 receives the multi-channel pulse current signal output by the photosensitive chip 1 and converts it into a pulse voltage signal, which is amplified and shaped before output.

[0028] The photosensitive chip 1 is fixed to the conductive tape substrate 2 by means of a conductive adhesive; the conductive tape substrate 2 is installed and fixed in the device housing by means of an insulating adhesive.

[0029] See Figure 1 In this embodiment, the photosensitive chip 1 is a quadrant photodiode, preferably a dual quadrant photodiode, which is used to convert the received laser signal into a pulse current signal. The amplifier circuit 3 can adopt a single hollow structure with an outer circle and an inner circle or an outer circle and an inner square. Figure 1 The figure shows the hollow structure of the outer circle and inner circle of the amplifier circuit 3; the amplifier circuit 3 is formed by integrating components such as a transistor core, an amplifier chip and a resistor on a circuit substrate through double-sided surface mounting, and is used to convert the multi-channel pulse current signal output by the photosensitive chip 1 into a pulse voltage signal and amplify and shape the output; the amplifier circuit 3 is also designed with welding holes 4, which are connected one-to-one with the tube socket pins 6 set on the device housing, so as to realize the connection between the amplifier circuit 3 and the signal output electrical appliance through the tube socket pins 6.

[0030] The device housing includes a tube base 7 and a tube cap 13 . The amplifier circuit 3 with the photosensitive chip 1 is arranged on the tube base 7 . The tube cap 13 is installed on the tube base 7 and covers the amplifier circuit 3 .

[0031] The tube socket 7 comprises a tube socket base 5 and tube socket pins 6. The main body of the tube socket base 5 is a circular plate with a raised circular table II9 in the center and a raised annular table I8 on the periphery. A circular concave surface 10 is provided on top of table II9. The tops of table I8 and table II9 are coplanar and used to support and mount the amplifier circuit 3, enhancing its resistance to high overloads. The height of table I8 and table II9 is ​​based on the space required for the layout of electronic components on the back of the amplifier circuit 3. The concave surface 10 is used to position and mount the conductive tape substrate 2 containing the photosensitive chip 1. The depth of the concave surface 10 is consistent with the thickness of the conductive tape substrate 2, and the diameter of the concave surface 10 is larger than the diameter of the conductive tape substrate 2, providing a clearance fit between the conductive tape substrate 2 and the concave surface 10. The tube socket pins 6 are made of glass insulation material and sintered to the metal base of the tube socket 7 to achieve electrical connection.

[0032] The tube cap 13 includes a tube cap base 11 and an optical window 12 opened in the center of the tube cap base 11. The tube cap base 11 and the optical window 12 are formed into a device shell tube cap 13 by welding or brazing, which must meet the airtightness requirements and have the characteristic of resisting high overload. An annular inclined buffer structure 14 is provided on the top of the tube cap base 11. The inclined buffer structure 14 is inclined outward and downward to enhance the high overload resistance of the tube cap base 11. The optical window 12 is used to ensure the incidence of the laser signal.

[0033] The tube base 7 and the tube cap 13 are sealed by laser sealing, parallel sealing or energy storage sealing to ensure that the photosensitive chip and the amplifier circuit are hermetically sealed with the outside world.

[0034] The preparation method of the flat quadrant laser detector assembly as described above is as follows: the photosensitive chip 1 is fixed to the conductive tape substrate 2 by a conductive adhesive; the conductive tape substrate 2 is installed and fixed on the concave surface 10 structure of the tube seat base 5 by an insulating adhesive, and the two meet the concentricity requirements; the amplifier circuit 3 is installed and fixed on the table I8 and table II9 of the tube seat base 5 by an insulating adhesive, and the welding holes 4 correspond to the tube seat pins 6 one by one; the electrodes of each quadrant of the photosensitive chip 1 and the corresponding ports of the amplifier circuit 3 are connected through the intermediate leads of the conductive tape substrate 2 solder points, and the ports of the amplifier circuit 3 are connected to the corresponding tube seat pins 6 through the welding holes 4; the tube cap base 11 and the light window 12 are formed into a device shell tube cap 13 by melting or brazing, which meets the airtightness requirements; the tube seat 7 and the tube cap 13 are sealed by laser sealing, parallel sealing or energy storage sealing, etc., which must meet the airtightness requirements.

[0035] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing a flat quadrant laser detector assembly, characterized in that: The flat quadrant laser detector assembly comprises a photosensitive chip (1), an amplifier circuit (3) and a device housing; the photosensitive chip (1) and the amplifier circuit (3) are both arranged in the device housing, the amplifier circuit (3) is a hollow structure with a central opening, the photosensitive chip (1) is located at the central opening of the amplifier circuit (3), the photosensitive chip (1) and the amplifier circuit (3) are coplanar with each other, the photosensitive chip (1) receives the laser signal and converts it into a pulse current signal, the amplifier circuit (3) receives the multi-channel pulse current signal output by the photosensitive chip (1) and converts it into a pulse voltage signal, amplifies and shapes it, and outputs it; the photosensitive chip (1) is fixed to the conductive band substrate (2); ...) The chip (1) is a dual four-quadrant photodiode, and the amplifier circuit (3) is a single-chip hollow structure with an outer circle and an inner circle or an outer circle and an inner square. The amplifier circuit (3) is formed by integrating a transistor core, an amplifier chip and a resistor element on a circuit substrate through double-sided surface mounting. The amplifier circuit (3) is also designed with welding holes (4), and the welding holes (4) are connected to the tube base pins (6) provided on the device housing in a one-to-one correspondence, so as to realize the connection between the amplifier circuit (3) and the signal output electrical appliance through the tube base pins (6). The device housing includes a tube base (7) and a tube cap (13), and the amplifier circuit (3) with the photosensitive chip (1) is arranged on the tube base (7), and the tube cap (13) is installed on the tube base (7). At the same time, the cover is arranged above the amplifier circuit (3); the tube seat (7) includes a tube seat base (5) and a tube seat pin (6); the body of the tube seat base (5) is a circular plate, with a raised circular table II (9) in the center of the body, a raised annular table I (8) on the periphery of the body, and a circular concave surface (10) is provided on the top of the table II (9); the tops of the table I (8) and the table II (9) are coplanar and are used to support the installation of the amplifier circuit (3); the heights of the table I (8) and the table II (9) are based on the space required for the layout of the electronic components on the back of the amplifier circuit (3); the concave surface (10) is used to position and install the conductive substrate (2) containing the photosensitive chip (1), and the concave surface (10) is used to position and install the conductive substrate (2) containing the photosensitive chip (1). The depth of the surface (10) is consistent with the thickness of the conductive tape substrate (2), the diameter of the concave surface (10) is larger than the diameter of the conductive tape substrate (2), and the conductive tape substrate (2) and the concave surface (10) are clearance-matched; the tube base pin (6) is provided with glass insulating material and is sintered with the metal base of the tube base (7) for realizing electrical connection; the tube cap (13) includes a tube cap base (11) and a light window (12) opened in the center of the tube cap base (11); a ring-shaped inclined buffer structure (14) is provided on the top of the tube cap base (11), and the inclined buffer structure (14) is inclined outward and downward for enhancing the high overload resistance of the tube cap base (11); the light window (12) is used for the incidence of laser signals; The preparation method comprises the following steps: fixing the photosensitive chip (1) to the conductive tape substrate (2) by means of a conductive adhesive; fixing the conductive tape substrate (2) to the concave surface (10) of the tube base (5) by means of an insulating adhesive, and the two satisfying the concentricity requirement; fixing the amplifier circuit (3) to the table I (8) and table II (9) of the tube base (5) by means of an insulating adhesive, and the welding holes (4) correspond to the tube base pins (6) one by one; the electrodes of each quadrant of the photosensitive chip (1) correspond to the corresponding amplifier circuits. The ports of the large circuit (3) are connected via transfer leads on the solder joints of the conductive substrate (2), and the ports of the amplifier circuit (3) are connected to the corresponding tube base pins (6) via the solder holes (4); the tube cap base (11) and the light window (12) are sealed or brazed to form a device shell tube cap (13), meeting the airtightness requirements; the tube base (7) and the tube cap (13) are sealed by laser sealing, parallel sealing or energy storage sealing, meeting the airtightness requirements, and are used for airtight sealing between the photosensitive chip and the amplifier circuit and the outside world.

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