Unlock instant, AI-driven research and patent intelligence for your innovation.

Wafer bonding method

A wafer bonding and wafer technology, used in electrical components, semiconductor/solid-state device manufacturing, circuits, etc., to solve the problem of forming holes on the wafer surface, wafer bonding edge defects, reducing device yield and reliability, etc. problem, to achieve the effect of reducing void rate, improving void yield, and reducing void formation

Pending Publication Date: 2020-12-08
BEIJING U PRECISION TECH
View PDF4 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

This method is easy to operate and relatively low in cost, and has attracted the attention of researchers and industries, but the problem is that a large number of voids (Void) often appear in the bonding interface of the wafer during the low-temperature annealing process, and these voids are serious. Reduced device yield and reliability
The current nitrogen drying method is usually carried out at room temperature, but the chemical cleaning agent or moisture remaining on the wafer surface after cleaning will be volatilized by heat during the subsequent annealing process, and holes will also be formed on the wafer surface
[0007] Chinese patent application CN2018100965559 discloses a nitrogen cleaning method, which solves the problem of edge defects during wafer bonding by cleaning the chamfers on the back and front of the wafer under nitrogen protection
This method only partially cleans the wafer, and the nitrogen protection cleaning is also carried out at room temperature, which cannot solve the problem of voids caused by the cleaning agent and moisture residue on the wafer surface

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Wafer bonding method

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0051] The first step: select two silicon wafers, and there are several bonding regions on the two wafers respectively.

[0052] Step 2: Perform plasma activation treatment on the surfaces of the two wafers respectively. Maintain the nitrogen pressure at 5~10×10 -2Between Pa, start to discharge again and apply an AC voltage of 220V, and the discharge power is 200W.

[0053] The third step: cleaning treatment. The two wafers after the plasma activation treatment were cleaned separately, the cleaning agent was RCA solution (a mixture of ammonia, hydrogen peroxide and water, the ratio was 1:1:5), the reagent temperature was 23°C, and the flow rate was 0.5 L / min. The wafer rotation speed was 600 rpm.

[0054] Step 4: Perform two-phase flow jetting treatment on the cleaned wafer. The nitrogen flow rate is 10L / min, and the deionized water flow rate is 50mL / min. After mixing, they are sprayed out through the nozzle to form a two-phase deionized water flow entrained with micro-na...

Embodiment 2

[0061] The first step: select two silicon wafers, and there are several bonding regions on the two wafers respectively.

[0062] Step 2: Perform plasma activation treatment on the surfaces of the two wafers respectively. Maintain the nitrogen pressure at 5~10×10 -2 Between Pa, start to discharge again and apply an AC voltage of 220V, and the discharge power is 200W.

[0063] The third step: cleaning treatment. The two wafers after the plasma activation treatment were cleaned separately, the cleaning agent was RCA solution (a mixture of ammonia, hydrogen peroxide and water, the ratio was 1:1:5), the reagent temperature was 23°C, and the flow rate was 0.5 L / min. The wafer rotation speed was 600 rpm.

[0064] Step 4: Perform two-phase flow jetting treatment on the cleaned wafer. The nitrogen flow rate is 100L / min, and the deionized water flow rate is 150mL / min. After mixing, they are sprayed out through the nozzle to form a two-phase deionized water flow entrained with micro...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention provides a wafer bonding method. The wafer bonding method comprises the following steps: carrying out plasma activation treatment on a wafer to be bonded; cleaning the wafer subjected tothe plasma activation treatment; performing nitrogen drying on the cleaned wafer in a gradient heating mode; and carrying out pre-bonding and bonding on the dried wafer. According to the method, thewhole wafer is subjected to nitrogen drying treatment by adopting hot nitrogen gradient heating so as to eliminate or reduce the formation of a cavity between the two bonded wafers.

Description

technical field [0001] The invention relates to a wafer bonding method and belongs to the technical field of semiconductor manufacturing. Background technique [0002] With the development of semiconductor technology, silicon wafers have extensive and important applications in the semiconductor industry. The connection between wafers usually adopts bonding technology, which uses the bonding force of atoms on the bonding surface of two wafers, and after treatment, the atoms on the bonding surface react to produce covalent bonding and achieve a certain bonding strength. [0003] Wafer bonding technology refers to cleaning the wafer first without adding adhesives, then performing wafer surface activation treatment, and then pre-bonding two wafers, and then undergoing some physical and chemical reactions to make the wafer The bonded wafer pairs form a single entity. Commonly used bonding techniques include anodic bonding and eutectic bonding. [0004] With the development of ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): H01L21/18
CPCH01L21/187
Inventor 张凇铭司伟
Owner BEIJING U PRECISION TECH