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CN-122002711-A - Crystal oscillator manufacturing method and crystal oscillator

CN122002711ACN 122002711 ACN122002711 ACN 122002711ACN-122002711-A

Abstract

The invention relates to the technical field of crystal oscillator manufacturing, and discloses a crystal oscillator manufacturing method and a crystal oscillator, wherein the crystal oscillator comprises an IC body, an IC bonding wire, a resonator, an IC fixing adhesive, a first layer PCB, a second layer PCB, soldering tin and black glue, wherein the first layer PCB and the second layer PCB are connected through reflow soldering to form a base, a closed cavity with a concave bottom is arranged in the middle of the base, the resonator is welded on the upper surface of the first layer PCB through soldering tin and seals the top of the closed cavity, and the IC body is fixed in the closed cavity through the IC fixing adhesive.

Inventors

  • DUAN MINGMENG
  • LIN XIAOGANG
  • PENG JIANWEN
  • LIN BINGLUN

Assignees

  • 应达利电子股份有限公司

Dates

Publication Date
20260508
Application Date
20260104

Claims (8)

  1. 1. The manufacturing method of the crystal oscillator is characterized by comprising the following steps: s1, cavity molding, namely aligning and attaching a first layer of PCB (5) and a second layer of PCB (6) through soldering tin (7), and forming a closed cavity structure with a bottom recess after reflow soldering; s2, attaching the resonator (3), namely welding the resonator (3) to the upper surface of the first layer of PCB (5) through soldering tin (7), and sealing the top opening of the closed cavity and then performing reflow soldering; S3, fixing the chip, namely fixing the IC body (1) in the closed cavity on the back of the resonator (3) through a die bond adhesive; s4, electric interconnection, namely bonding and connecting the IC body (1) with an internal welding spot on the second layer PCB (6) through lead bonding of the IC bonding wire (2); s5, sealing the cavity, namely filling the sealed cavity with black glue (8), and encapsulating the IC bonding wire (2) and the IC body (1).
  2. 2. The method for manufacturing a crystal oscillator according to claim 1, wherein the first layer PCB (5) and the second layer PCB (6) are provided with hollowed-out areas for accommodating the solder paste, so as to control the flow and the forming height of the solder paste after reflow soldering.
  3. 3. A method of manufacturing a crystal oscillator according to claim 1, characterized in that the first layer PCB (5) and the second layer PCB (6) are HDI boards comprising at least one blind via, which is filled with a conductive material for realizing an electrical interconnection between layers.
  4. 4. A method of manufacturing a crystal oscillator according to claim 1, characterized in that the solder paste is distributed in a ring shape around the periphery of the soldering area of the resonator (3).
  5. 5. The method of claim 1, wherein the encapsulant of the die attach adhesive is one or more of underfill, epoxy, and silicone, and the injection is dispensing.
  6. 6. The method according to claim 1, further comprising, after the step S5, step S6: And (3) mounting external passive elements, namely welding at least one inductor on the outer surfaces of the first layer PCB (5) and the second layer PCB (6).
  7. 7. The method of claim 1, further comprising the step of S0 before S1: And manufacturing built-in impedance matching networks on the first layer PCB (5) and the second layer PCB (6).
  8. 8. A crystal oscillator manufactured by the manufacturing method according to any one of claims 1-7, comprising an IC body (1), an IC bonding wire (2), a resonator (3), an IC fixing adhesive (4), a first layer PCB (5), a second layer PCB (6), solder (7) and black adhesive (8), wherein the first layer PCB (5) and the second layer PCB (6) are connected through reflow soldering to form a base, a closed cavity with a concave bottom is arranged in the middle of the base, the resonator (3) is welded on the upper surface of the first layer PCB (5) through solder (7) and seals the top of the closed cavity, the IC body (1) is fixed in the closed cavity through the IC fixing adhesive (4) and is electrically connected with the first layer PCB (5) through the IC bonding wire (2), and the black adhesive (8) is filled in the closed cavity and encapsulates the IC body (1) and the IC bonding wire (2).

Description

Crystal oscillator manufacturing method and crystal oscillator Technical Field The invention relates to the technical field of crystal oscillator manufacturing, in particular to a crystal oscillator manufacturing method and a crystal oscillator. Background The crystal oscillator is used as a high-precision and high-stability frequency source and is widely applied to various fields of communication equipment, computers, consumer electronics, industrial control, automobile electronics and the like, and the core working principle is that the piezoelectric effect of quartz crystal is utilized to generate stable mechanical oscillation, and the stable mechanical oscillation is converted into electric signals through an oscillation Integrated Circuit (IC) to be output. In the conventional miniaturized surface-mounted crystal oscillator (SMD type), a typical structure is usually packaged by ceramic, and when the crystal oscillator is manufactured, special ceramic clay materials are needed to be used at first, the ceramic base with a specific groove or cavity is formed by pressing and forming through a die and sintering at high temperature, the groove has the main functions of accommodating and fixing an oscillating IC chip, then, a quartz crystal wafer is sealed with the ceramic base, the crystal wafer, the oscillating IC and external pins are electrically connected through an internal lead, and finally, a metal or ceramic cover plate is covered to complete airtight packaging so as to ensure that an internal element stably works in an inert gas environment. However, this conventional ceramic base manufacturing process has the following disadvantages: The preparation of ceramic green bodies, the development and maintenance of special dies and the high-temperature sintering process all require higher equipment investment and energy consumption, so that the production cost is difficult to further reduce; the mold has long mold opening and modifying period, once the mold is designed and shaped, the size and the shape of the cavity are not easy to change, and the customization requirement of customers on the size or the internal layout of the product is difficult to respond quickly; The ceramic base is mainly used for physical support and airtight space functions, and additional passive elements are difficult to directly integrate on the ceramic base or a more complex multilayer interconnection structure is realized, so that the space for product function integration and performance optimization is limited. In order to solve the above-mentioned drawbacks, a new crystal oscillator manufacturing process is needed. Disclosure of Invention The invention provides a manufacturing method of a crystal oscillator and the crystal oscillator, and solves the technical problems that a traditional ceramic base in the related art is high in production cost and difficult to provide customized requirements. The invention provides a manufacturing method of a crystal oscillator, which comprises the following steps: S1, cavity molding, namely aligning and attaching a first layer of PCB and a second layer of PCB through soldering tin, and forming a closed cavity structure with a bottom recess after reflow soldering; s2, attaching the resonator, namely welding the resonator to the upper surface of the first layer of PCB through soldering tin, sealing the top opening of the closed cavity, and then performing reflow soldering; s3, fixing the chip, namely fixing the IC body in the closed cavity on the back of the resonator through a die bond adhesive; s4, electric interconnection, namely bonding and connecting the IC body with an internal welding spot on the second layer of PCB through wire bonding of the IC bonding wire; s5, sealing the cavity, namely filling the sealed cavity with black glue, and encapsulating the IC bonding wire and the IC body. According to the invention, the first layer PCB and the second layer PCB are provided with hollowed-out areas for accommodating the solder paste in advance so as to control the flow and the forming height of the solder paste after reflow soldering. As a further scheme of the invention, the first layer PCB and the second layer PCB are HDI boards comprising at least one blind hole, and the blind hole is filled with conductive materials for realizing interlayer electrical interconnection. As a further proposal of the invention, the solder paste is distributed on the periphery of the welding area of the resonator in a ring shape. As a further scheme of the invention, the packaging colloid of the die bonding glue is one or more of underfill, epoxy resin and silica gel, and the injection mode is dispensing. As a further scheme of the invention, after the step S5, the method further comprises the step S6 of: and (3) mounting external passive elements, namely welding at least one inductor on the outer surfaces of the first layer of PCB and the second layer of PCB. As a further scheme of the invention, before