TW201436028A - Wafer edge protector - Google Patents

Abstract

A wafer edge protector used in an inductively coupled plasma reactive ion etching instrument for the manufacturing of GaN semiconductor devices and circuits. The wafer edge protector comprises a ring clamp, which has a first inner diameter and a second inner diameter, and the ring clamp covers the edges of a wafer and a wafer carrier to clamp the wafer and the wafer carrier and to prevent damage on the edges of the wafer and the wafer carrier during the etching process.

Description

Wafer edge protector

The present invention relates to a wafer edge protection device, and more particularly to a wafer edge protection device for use in an inductively coupled plasma ion etching machine for a gallium nitride semiconductor device and a circuit process.

The inductively coupled plasma reactive ion etch method is commonly used in the fabrication of compound semiconductor wafers. The etched semiconductor semiconductor wafer must be fixed on a wafer holder as a wafer carrier. The etching is performed together with the crystal holder fixed in the etching machine. The fixture for fixing the wafer and the crystal holder in the prior art is usually a claw type wafer fixture. The claw type wafer fixture generally has six or eight fingers arranged in a surrounding manner for fixing the semiconductor crystal. Circles and crystal holders; due to the use of higher bias power during the etching of the back side of the compound semiconductor wafer, the edge of the wafer is often damaged during the etching process, so that the yield of the product cannot be improved, and the crystal holder carrying the semiconductor wafer is also Increased production costs due to damage to the edges due to exposure to the plasma and frequent replacement.

The main object of the present invention is to provide a wafer edge protection device for use in a semiconductor wafer plasma ion etching process, so that the edge of the semiconductor wafer is not easily damaged, and the crystal holder can be protected from etching substances during the etching process. Therefore, the yield of the product can be improved, and the service life of the crystal seat can be prolonged to save the process cost.

To achieve the above object, the present invention provides a wafer edge protection device for Mounted in an inductively coupled plasma ion etching machine, the wafer edge protection device has an annular clamping portion, wherein the annular clamping portion has a first inner diameter and a second inner diameter, covering a semiconductor wafer And an edge of a crystal holder for holding the semiconductor wafer and the crystal holder, and protecting the edges of the semiconductor wafer and the crystal holder from being damaged during the etching process.

In implementation, the aforementioned first inner diameter is between 40 mm and 200 mm.

In implementation, the aforementioned second inner diameter is between 50 mm and 1000 mm.

In implementation, the aforementioned annular clamping portion is made of a ceramic material.

In implementation, the wafer is a compound semiconductor gallium nitride (GaN) wafer with a size between 50 mm and 200 mm.

In implementation, the compound semiconductor gallium nitride wafer is fixed to a crystal holder having a size between 50 mm and 200 mm.

In the implementation, the crystal holder for fixing the gallium nitride wafer is made of a sapphire material substrate, a glass material substrate or a tantalum carbide material substrate.

For a better understanding of the features and functions of the present invention, the embodiments are described in detail below with reference to the drawings.

10‧‧‧Inductively coupled plasma ion etching machine

100‧‧‧ Wafer edge protection device

101‧‧‧Ring clamping

102‧‧‧First inner diameter

103‧‧‧Second inner diameter

104‧‧‧ Wafer edge coverage width

110‧‧‧Semiconductor wafer

120‧‧‧crystal seat

1A to 1C are schematic and partial cross-sectional enlarged views of an embodiment of a wafer edge protection device provided by the present invention.

Please refer to FIGS. 1A to 1C , which are schematic diagrams of an embodiment of a wafer edge protection device according to the present invention, wherein FIG. 1C is an enlarged view of a portion circled by a broken line C in FIG. 1B. The edge protection device 100 is mounted on an inductively coupled plasma ion etching machine The ring 10 has a first inner diameter 102 and a second inner diameter 103. The edge protection device 100 covers a semiconductor wafer 110 and a The edge of the crystal holder 120 is used to sandwich the semiconductor wafer 110 and the crystal holder 120, and protect the edges of the semiconductor wafer 110 and the crystal holder 120 from being damaged during the etching process.

In the embodiment provided by the present invention, the opening formed by the first inner diameter 102 is used as an etched area of the semiconductor wafer, and the space formed by the second inner diameter 103 needs to completely cover the entire wafer and the crystal seat. The invention can be applied to compound semiconductor gallium nitride wafers ranging in size from 2 吋 (50 mm) to 8 吋 (200 mm), and gallium nitride (GaN) wafers containing half of insulating 4H tantalum carbide (4H) a gallium nitride-based epitaxial layer of a -SiC) or 6H tantalum carbide (6H-SiC) substrate, and the size of the crystal holder used to carry the wafer must be greater than or equal to the wafer size, so the first inner diameter 102 can be Between 40 mm and 200 mm, and the second inner diameter 103 can be between 50 mm and 1000 mm; for example, the current mainstream size of a gallium nitride wafer production line is 4 吋 (100 mm) wafer. The commonly used crystal holder for a gallium nitride wafer is a sapphire crystal holder made of a conductive material, a glass crystal holder or a silicon carbide crystal holder, and the size can be 4 吋 (100 mm) to 8 吋 (200 mm). Therefore, in the preferred embodiment of the wafer edge protection device provided by the present invention, the range of the first inner diameter 102 is between Between 90 mm and 100 mm, and the second inner diameter 103 can range from 100 mm to 200 mm. The 4 吋 wafer edge coverage width 104 covered by this design is about 1.5 to 5.0 mm; The range of the inner diameter and the second inner diameter can be adjusted according to the size of the wafer and the crystal seat; in order to protect the function of the wafer and the edge of the crystal seat, the annular clamping portion 101 has high hardness and high etching resistance. High corrosion resistance materials are preferred, with ceramic materials being the best choice.

Therefore, the wafer edge protection device provided by the present invention covers the edge of the wafer and the crystal seat, so that the edge of the semiconductor wafer is not easily damaged, and the edges of the wafer and the crystal holder are covered and protected for bonding. The paste or wafer of the wafer or wafer is not exposed to etching during the etching process. In the material, it is possible to prevent the glue and the wax from being etched and leaking the contaminated wafer, and at the same time, the crystal seat can be prevented from being damaged by the etching material during the etching process.

In summary, the wafer edge protection device provided by the present invention can achieve the intended purpose, and protect the wafer and the edge of the crystal holder in the plasma ion etching process, thereby improving the yield of the product and extending the crystal seat. Service life, which in turn saves process costs. It does have the value of industrial use, and it submits invention patent applications according to law.

The above description and the drawings are merely illustrative of the embodiments of the present invention, and those skilled in the art can still make equivalent local variations and modifications without departing from the spirit and scope of the invention.

10‧‧‧Inductively coupled plasma ion etching machine

100‧‧‧ Wafer edge protection device

101‧‧‧Ring clamping

102‧‧‧First inner diameter

103‧‧‧Second inner diameter

110‧‧‧Semiconductor wafer

120‧‧‧crystal seat

Claims (8)

A wafer edge protection device for mounting in an inductively coupled plasma ion etching machine, the wafer edge protection device having an annular clamping portion, wherein the annular clamping portion has a first inner diameter and a second The inner diameter covers an edge of a semiconductor wafer and a crystal holder for holding the semiconductor wafer and the crystal holder, and protects the semiconductor wafer and the edge of the crystal holder from being damaged during the etching process. The wafer edge protection device of claim 1, wherein the first inner diameter is between 40 mm and 200 mm. The wafer edge protection device of claim 1, wherein the second inner diameter is between 50 mm and 1000 mm. The wafer edge protection device of claim 1, wherein the annular clamping portion is made of a ceramic material. The wafer edge protection device of claim 1, wherein the wafer is a compound semiconductor gallium nitride (GaN) wafer having a size between 50 mm and 200 mm. The wafer edge protection device according to claim 5, wherein the compound semiconductor gallium nitride (GaN) wafer comprises a semi-insulating 4H tantalum carbide (4H-SiC) or 6H tantalum carbide (6H-SiC). The substrate is a gallium nitride-based epitaxial layer. The wafer edge protection device of claim 6, wherein the compound semiconductor gallium nitride wafer is fixed to a crystal holder having a size between 50 mm and 200 mm. The wafer edge protection device of claim 7, wherein the crystal holder is made of a sapphire material substrate, a glass material substrate or a tantalum carbide material substrate.