半导体器件的终端结构及半导体器件

Abstract

本实用新型涉及一种半导体器件的终端结构及半导体器件，其包括第一导电类型衬底、第一导电类型外延层、第二导电类型第一终端柱和第二导电类型第二终端柱，第一导电类型外延层设置在第一导电类型衬底正面，第二导电类型第一终端柱至少设置有两个，沿第一方向依次排布设置并且其沿第一方向上的厚度逐步递增，第二导电类型第二终端柱，至少设置有两个，设置在所述第二导电类型第一终端柱背向半导体器件元胞区一侧上，所述第二导电类型第二终端柱沿第一方向依次排布设置并且沿第一方向上的厚度逐步递减，本实用新型具有终端区的超结柱的厚度沿第一方向曲线分布，提高终端区的耐压，发生提前击穿的可能性减少，提高了器件的可靠性的效果。

Claims

1. A termination structure for a semiconductor device, characterized in that, include: First conductivity type substrate; A first conductivity type epitaxial layer is disposed on the front side of a first conductivity type substrate; The second conductive type first terminal post is provided with at least two of them, which are arranged sequentially along the first direction and their thickness gradually increases along the first direction; At least two second terminal posts of the second conductivity type are provided, which are disposed on the side of the first terminal post of the second conductivity type facing away from the semiconductor device cell region. The second terminal posts of the second conductivity type are arranged sequentially along the first direction and their thickness gradually decreases along the first direction.

2. The termination structure for a semiconductor device according to claim 1, wherein The second conductivity type first terminal post is arranged in x numbers along the first direction starting from the nearest semiconductor device cell region, wherein the thickness of the xth second conductivity type first terminal post along the first direction is not less than the thickness of the (x-1)th second conductivity type first terminal post along the first direction, and the thickness of the xth second conductivity type first terminal post is greater than the thickness of the first second conductivity type first terminal post.

3. The termination structure for a semiconductor device according to Claim 1, wherein The second terminal post of the second conductive type is arranged in y units along the first direction starting from the first terminal post of the second conductive type. The thickness of the yth second terminal post of the second conductive type along the first direction is not greater than the thickness of the (y-1)th second terminal post of the second conductive type along the first direction, and the thickness of the yth second terminal post of the second conductive type is less than the thickness of the first second terminal post of the second conductive type.

4. The termination structure for a semiconductor device according to claim 1, wherein The first terminal post of the second conductivity type and the second terminal post of the second conductivity type have the same length along the second direction.

5. The termination structure for a semiconductor device according to claim 1, wherein The number of first terminal posts of the second conductivity type is less than the number of second terminal posts of the second conductivity type.

6. The termination structure for a semiconductor device according to claim 1, wherein The first conductive type terminal post is set between two adjacent first conductive type terminal posts, between two adjacent second conductive type terminal posts, and between adjacent first conductive type terminal posts and second conductive type terminal posts. The ratio of the thickness of the second conductive type first terminal post to its adjacent first conductive type terminal post near the cell region along the first direction is the same as the ratio of the thickness of the second conductive type second terminal post to its adjacent first conductive type terminal post near the cell region along the first direction.

7. The termination structure for a semiconductor device according to claim 1, wherein A field oxide layer is provided on the front side of the first conductivity type epitaxial layer, and the field oxide layer is disposed in the region of the second conductivity type first terminal post and the second conductivity type second terminal post on the first conductivity type epitaxial layer.

8. A semiconductor device, characterized by It includes a cell region and a terminal region, wherein the terminal region includes the terminal structure of the semiconductor device according to any one of claims 1-7, and the cell region and the terminal region share the first conductivity type substrate and the first conductivity type epitaxial layer; The cell region includes: a second conductivity type pillar, at least two of which are provided, extending from the front side to the back side of the first conductivity type epitaxial layer; and a second conductivity type body region, which is provided on the front side of the first conductivity type epitaxial layer and located within the first conductivity type epitaxial layer. The first conductivity type source region is disposed on the front side of the second conductivity type body region and located within the second conductivity type body region; A gate structure is disposed between two adjacent pillars of the second conductivity type and on the front side of the epitaxial layer of the first conductivity type. An insulating dielectric layer is disposed on the front side of the second conductive type body region. A plurality of metal contact through holes are formed in the insulating dielectric layer. The plurality of metal contact through holes are correspondingly disposed with the second conductive type pillar and are connected to the second conductive type pillar and the first conductive type source region. A front metal layer is disposed on the front side of the insulating dielectric layer, and the portion of the front metal layer located at the metal contact via extends into the metal contact via until it fills the metal contact via. A back metal layer is disposed on the back side of the first conductivity type substrate.

9. The semiconductor device of claim 8, wherein, The thickness of the second conductive type post along the first direction is not greater than the thickness of the second conductive type first terminal post along the first direction.

10. The semiconductor device of claim 8, wherein, The gate structure includes a first trench formed on the front side of the first conductivity type epitaxial layer, a gate is disposed in the first trench, and a gate oxide layer is disposed between the gate and the inner wall of the first trench.

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