Two-way ultralow capacitance transient voltage suppressor and production method thereof

Abstract

The invention relates to a two-way ultralow capacitance TVS (Transient Voltage Suppressor) and a production method thereof. The TVS comprises a semiconductor substrate of a first conductive type, a first epitaxial layer of a second conductive type, a third epitaxial layer of the first conductive type, a first buried layer of the second conductive type, a first doped region of the second conductive type, a second doped region of the first conductive type, a first groove, a second groove, a first insulating medium, a third groove and an active region, wherein the first buried layer is formed between the first epitaxial layer and the third epitaxial layer; the first doped region is formed by being opposite to the first buried layer in the third epitaxial layer; the second doped region is formed in the third epitaxial layer and is not opposite to the first buried layer; the first groove extends to the inside of the semiconductor substrate from the surface of the third epitaxial layer; the second groove extends from the surface of the third epitaxial layer and penetrates through the third epitaxial layer; the first groove and the second groove are filled with the first insulating medium; the third groove extends from the surface of the third epitaxial layer and penetrates through the first buried layer to the inside of the first epitaxial layer; the active region is formed by annealing in-situ polycrystalline silicon loaded in the third groove.

Description

technical field [0001] The invention relates to the technical field of semiconductor microelectronics, in particular, the invention relates to a bidirectional ultra-low capacitance transient voltage suppressor and a manufacturing method thereof. Background technique [0002] Transient Voltage Suppressor TVS (Transient Voltage Suppressor) is a high-efficiency circuit protection device developed on the basis of voltage regulator tubes. The shape of TVS diodes is the same as that of ordinary Zener tubes. However, due to the special structure and process design, the transient response speed and surge absorption capacity of TVS diodes are much higher than ordinary Zener tubes. For example, TVS diodes have a response time of only 10 -12 seconds, and can absorb surge power up to several thousand watts. Under reverse application conditions, when subjected to a high-energy large pulse, the working impedance of the TVS diode will quickly drop to an extremely low conduction value, al...

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Problems solved by technology

[0009]1. Two sets of chips need to be packaged in series, which is expensive;

[0010]2. For smaller packages, two sets of chips cannot be packaged at the same time

[0013]1. The two channel terminals must be led out from the front side at the same time, resulting in a larger chip area, which is not suitable for smaller packages;

[0014]2. When packaging, the two channel ends must each have a metal wire, which is expensive

[0017]1. Two chips need to be placed on each base island, which leads to a higher probability of packaging defects and increases the cost of diebonding;

[0018]2. When encapsulating, the two channels must each have a metal wire, which is expensive;

[0019]3. The integrated packaging of multiple chips requires more space and increases the overall size, which is not suitable for smaller packages

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