CN-115985788-B - All-glass passivation diode and production method thereof

Abstract

The invention provides a production method of an all-glass passivated diode, which comprises the following steps of (a) preparing a chip, (b) preparing raw materials, (c) preparing software, presetting laser parameters and raw material parameters, completing preset information of laser sintering according to different diode design requirements by computer modeling software through computer aided design technology CAD, transmitting the preset information to a semiconductor laser, (ii) uniformly paving powder, (iii) sintering by laser, (iv) recycling, and (v) eliminating glue discharge. According to the production method of the all-glass passivation diode, the laser forming technology is adopted to prepare the glass protection seal of the PN junction of the diode, the sintering of the diode glass is precisely controlled, the comprehensive protection seal of the PN junction of the diode is completed once, and no potential fault source exists. The invention also provides an all-glass passivation diode produced by the all-glass passivation diode production method.

Inventors

• CHEN JINGCANG

Assignees

• 上海百功微电子有限公司

Dates

Publication Date

20260505

Application Date

20230129

Claims (3)

1. 1. The production method of the all-glass passivation diode is characterized by comprising the following steps of: preparation: (a) The preparation of a chip, namely, after the diode (1) is processed according to the requirement, a diode chip semi-finished product with a P surface provided with a groove and a PN junction surface exposed and a single chip in a half-cut form is formed; (b) Preparing raw materials, namely uniformly mixing passivation glass powder and a curing agent according to the requirement in proportion to obtain mixed powder of a diode packaging material, and then injecting the mixed powder into a powder spray head (2) matched with a semiconductor laser (3); (c) The method comprises the steps of software preparation, namely presetting laser parameters and raw material parameters, completing preset information of laser sintering according to design requirements of different diodes (1) by using computer modeling software through a Computer Aided Design (CAD), and transmitting the preset information to a semiconductor laser (3), wherein the preset information comprises that the laying position of passivation glass powder is the exposed position of a diode chip, and the CAD path of laser sintering is the PN junction position of the diode; Uniformly spreading powder, namely controlling the powder spray head (2) by computer modeling software according to preset information, controlling the deposition amount and the deposition position of a powder coating, uniformly spraying packaging materials around the PN junction of the diode, and realizing the full coverage of the packaging materials of the PN junction of the diode; the semiconductor laser (3) controls the laser beam (4) to carry out laser selective scanning on the packaging material powder layer paved at the PN junction position of the diode according to the two-dimensional CAD path arranged in the preset information, and the scanned packaging material powder is sintered together at the PN junction position due to the high temperature of the laser focus, so that a glass packaging thin layer is generated at the PN junction position of the diode, and the packaging material in the non-scanned area keeps original loose powder; after the first laser sintering is finished, the semiconductor laser (3) enters the next step according to the finishing condition of the preset sintering times, if the preset sintering times are finished, the powder spray head (2) is controlled, packaging material powder is uniformly sprayed on the periphery of the PN junction of the diode again, and then the laser sintering of a new layer is started again; (IV) recycling, namely removing and recycling unsintered packaging material powder from the diode (1) to obtain a diode chip subjected to encapsulation molding; Eliminating glue, namely heating and removing glue from the diode (1) after the protective sealing forming process to finish the glass protective sealing of the PN junction of the diode, so as to obtain the full-glass passivated diode component meeting the requirements; Cutting a semiconductor original chip into proper sizes according to the design size of a diode (1), removing bad phenomena such as microcrack, roughness, dislocation and the like of a cutting surface by utilizing an acid etching mode to enable a PN junction to be in a smooth state, preparing a silicon semiconductor wafer with PN diffusion, oxidizing the silicon semiconductor wafer, coating the wafer with photoresist, developing and cleaning to remove the photoresist at the edge part of each chip, and carrying out selective local chemical etching on an area which is not coated with the photoresist to form a diode chip semi-finished product with a groove on the P surface, exposing the PN junction surface and enabling a single chip to be in a semi-cutting state; The curing agent in the step (b) is high impact polystyrene glue, and the mass ratio of the passivation glass powder to the curing agent is 98wt% and 2wt% respectively; In the step (III), the diameter of the nozzle of the powder spray head (2) is 2 mu m, the thickness of the layer sprayed by a single time is 10 mu m, and the positioning precision of the powder spray is 2 mu m; the thickness of the glass powder paved in the step (c) is 20 mu m; In the step (III), the laser power is 3000W, X, the Y-axis resolution is 2 μm, and the Z-axis resolution is 10 μm.
2. 2. The method of producing a full glass passivation diode according to claim 1, wherein the heating and discharging process in the step (five) is specifically to remove the curing agent from the glass paste by using high temperature, so that the passivation glass (5) is recombined and tightly combined with the periphery of the PN junction of the diode.
3. 3. An all-glass passivated diode produced by the all-glass passivated diode production method of any one of claims 1 and 2.

Description

All-glass passivation diode and production method thereof Technical Field The invention relates to the technical field of photoelectronic packaging, in particular to an all-glass passivation diode and a production method thereof. Background At present, a semiconductor diode mostly adopts passivation glass to protect the exposed section of a P-N junction of a diode chip, wherein the most excellent mode is a glass protection sealing sheet (GLASSPASSIVATEDPELLET, called GPP for short), and the mode is to carry out glass protection sealing and sintering glass on the exposed position of a PN junction of a diode semi-cut wafer so as to finish the protection sealing processing of the semi-cut surface of the chip. However, the GPP approach has several drawbacks, and is not optimal. The cut surface of the diode chip is in a half-cut shape with an opening on the P surface, so that the cut angle of the PN junction surface belongs to a negative cut angle type, and the passivation glass is not easy to complete by the glass protection and sintering in the GPP mode. The defects cause the problems that the diode chip is easy to age and break down at high temperature, and the potential fault source of the diode is formed. Disclosure of Invention Aiming at the technical problems, the invention aims to provide a production method of a full glass passivation diode, which utilizes a laser forming technology to prepare a glass protection seal of a diode PN junction, and controls the deposition amount, the glass powder laying position and the laying thickness of a glass coating on the PN junction by controlling the working parameters of a laser beam and the raw material parameters of passivation glass powder and a curing agent, so that the full glass cladding of the diode PN junction is finished at one time, and the glass passivation of the diode obtains the optimal performance. The invention also provides an all-glass passivation diode produced by the all-glass passivation diode production method. The technical scheme adopted by the invention is as follows: the production method of the all-glass passivation diode comprises the following steps: first, prepare work (A) Preparing a chip, namely processing the diode according to the requirement to form a semi-finished product of the diode chip with a P surface provided with a groove and a PN junction surface exposed, wherein a single chip is in a semi-cut form; (b) Preparing raw materials, namely uniformly mixing passivation glass powder and a curing agent according to the requirement in proportion to obtain mixed powder of a diode packaging material, and then injecting the mixed powder into a powder nozzle matched with a semiconductor laser; (c) The method comprises the steps of software preparation, namely presetting laser parameters and raw material parameters, completing preset information of laser sintering according to different diode design requirements by computer modeling software through Computer Aided Design (CAD), and transmitting the preset information to a semiconductor laser, wherein the preset information comprises that the laying position of passivation glass powder is the exposed position of a diode chip, and the CAD path of laser sintering is the PN junction position of the diode; Uniformly spreading powder, namely controlling the powder spray head, controlling the deposition amount and the deposition position of a powder coating by computer modeling software according to preset information, uniformly spraying packaging materials around the PN junction of the diode, and realizing the full coverage of the packaging materials of the PN junction of the diode; The semiconductor laser controls the laser beam to carry out laser selective scanning on the packaging material powder layer paved at the PN junction position of the diode according to the two-dimensional CAD path arranged in the preset information, and the scanned packaging material powder is sintered together at the PN junction position due to the high temperature of the laser focus, so that a glass packaging thin layer is generated at the PN junction position of the diode, and the packaging material in the area which is not scanned keeps original loose powder; After the first laser sintering is finished, the semiconductor laser enters the next step according to the finishing condition of the preset sintering times, if the preset sintering times are finished, the powder spray head is controlled, packaging material powder is uniformly sprayed on the periphery of the PN junction of the diode again, and then laser sintering of a new layer is started again; (IV) recycling, namely removing and recycling unsintered packaging material powder from the diode to obtain the diode chip subjected to encapsulation molding; and fifthly, eliminating glue discharge, namely heating and glue discharge treatment is carried out on the diode after the protective sealing forming process, so that glass protective sealing of PN juncti