JPS6289321A - Semiconductor pellet - Google Patents

Abstract

PURPOSE:To reduce the number of any defective products while preventing the crack 4 or the like due to mechanical stress such as dicing in case of cutting and separating pellets from a wafer from reaching the element functional part by means of providing the peripheral part of a pellet with grooves. CONSTITUTION:An element functional part 2 directly related to the operation of elements such as a junction, mesa groove for protecting P-N junction or improving the dielectric strength, as well as a depletion region expanding in operation and the like is situated in the central part of a semiconductor pellet (substrate) 1 while a groove 3 encircling the functional part 2 is provided in the space between the part 2 and the peripheral parts of pellet 1. AT this time, it is recommended to form the groove 3 around 1.5 times deeper compared with the depth of P-N junction of element functional part 2 by a process such as etching or the like under no effect of mechanical stress.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a semiconductor pellet, and particularly to the structure of the outer periphery of the semiconductor pellet.

[Conventional technology]

Conventionally, except for grooves such as bevels and mesas for improving device functionality, grooves for retaining functional parts have not been provided on the outer periphery of semiconductor pellets.

[Problem that the invention seeks to solve]

As mentioned above, conventional semiconductor pellets do not have a beak on the outer periphery of the pellet, so when cutting and separating the wafer into pellets, it is generally difficult to use a mechanical cutting method such as dicing. As shown in Figure 2, cracks 4 occur and sometimes reach the functional part 2, resulting in a defective product.

[Failure to solve the problem]

The semiconductor pellet of the present invention has a groove portion that surrounds the device function portion over the entire circumference of the pellet at an arbitrary position between the device function portion including the PN junction provided on the main surface and the depletion layer that expands during operation and the periphery of the pellet. It's cool.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1(a) is a longitudinal cross-sectional view of one embodiment of the present invention, FIG.
b) is a plan view of FIG. 1(a). Semiconductor pellet 1
There is an element functional part 2 in the center that is directly related to the operation of the element, such as a PN junction, a mesa groove for protecting the PN junction or improving breakdown voltage, and a depletion layer region that expands during operation. A groove 3 is provided between the pellet and the peripheral edge of the pellet. This groove part 3 is machined.

It is preferable to form the PN junction at least 15 times the depth of the PN junction in the element functional section using a method that does not apply mechanical stress such as chipping. Due to the groove portion 3, cracks caused by mechanical stress caused by dicing or the like when cutting and separating the semiconductor wafer into pellets are stopped without spreading from the peripheral edge of the pellet to the element functional portion.

〔Effect of the invention〕

As explained above, the present invention prevents cracks caused by mechanical stress such as dicing when cutting and separating pellets from a wafer from reaching the device functional parts by providing grooves on the outer periphery of the pellets. This has the effect of reducing the occurrence of defective products.

[Brief explanation of drawings]

FIG. 1(a) is a longitudinal cross-sectional view of a semiconductor pellet according to an embodiment of the present invention, and FIG. 1(b) is a plan view of FIG. 1(a).
Fig. 2(a) is a vertical cross-sectional view of a conventional semiconductor pellet;
FIG. 2(b) is a plan view of FIG. 2(a). 1... Semiconductor substrate, 2... Functional section, 3
... Vortex, 4... Crack. Agent Patent Attorney Uchi D゛ - Haya / Kuchi Kasumi Figure 1 (b) Figure 2 (α) Figure 2 (b)

Claims (1)

[Claims] In the semiconductor pellets cut and separated from the wafer,
A semiconductor pellet having a groove portion surrounding the element functional portion at an arbitrary position between the pellet peripheral edge and the element functional portion including a PN junction provided on the main surface of the pellet and a depletion layer that expands during operation. .