Reliable gap-filling process and apparatus for performing the process in the manufacturing of semiconductor devices

• US 20070026630A1
• Filed: 05/30/2006
• Published: 02/01/2007
• Est. Priority Date: 05/30/2005
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kwon, Kyoung-soo, Kim, Yong-kyu, Jeon, Jin-ho
• Granted Patent: US 7,446,367 B2
• Time in Patent Office: Days
• US Class Current: 438/424
• CPC Class Codes: H01L 21/76224 using trench refilling with dielectric materials trench filling with polycristalline silicon H01L21/763; together with vertical isolation, e.g. trench refilling in a SOI substrate H01L21/76264

Abstract

A reliable gap-filling process is performed in the manufacturing of a semiconductor device. An apparatus for performing the gap-filling process includes a chamber in which a wafer chuck is disposed, a plasma generator for generating plasma used to etch the wafer, an end-point detection unit for detecting the point at which the etching of the wafer is to be terminated, and a controller connected to the end-point detection unit. The end-point detection unit monitors the structure being etched at a region outside the opening that is to be filled, and generates in real time data representative of the layer that is being etched. As soon as an underlying layer is exposed and begins to be etched, an end-point detection signal is generated and the etching process is terminated. In the case in which the layer being etched is an oxide layer, a uniform etching is achieved despite any irregularity that exists in the thickness to which the oxide layer is formed.

Claims

1. A semiconductor device manufacturing apparatus comprising:

an etching chamber;

a chuck disposed in the etching chamber to support a substrate to be etched in the chamber;

a plasma generator operatively associated with the chamber to produce plasma from an etching gas, and provide the plasma within the etching chamber to etch a substrate supported on the chuck;

an end point detection unit that monitors the etching process in the etching chamber and based on the monitoring instantaneously determines when the etching process is to be terminated; and

a controller operatively connected to the end point detection unit and to the plasma generator so as to turn off the plasma generator when the end point detection unit determines that the etching process is to be terminated.

2. The semiconductor device manufacturing apparatus according to claim 1, wherein the end point detection unit comprises an optical sensor that senses light produced in the chamber during the etching process.

3. The semiconductor device manufacturing apparatus according to claim 2, wherein the end point detection unit comprises an analyzer connected to the optical sensor to determine the wavelength of light sensed by the optical sensor in the chamber during the etching process.

4. The semiconductor device manufacturing apparatus according to claim 1, wherein the end point detection unit comprises a gas sensor that senses gas emitted in the chamber during the etching process.

5. The semiconductor device manufacturing apparatus according to claim 4, wherein the end point detection unit comprises an analyzer connected to the gas sensor to determine characteristics of the gas sensed by the gas sensor in the chamber during the etching process.

6. The semiconductor device manufacturing apparatus according to claim 1, wherein the end point detection unit comprises:

a sensor that monitors a condition of the etching process;

an analyzer operatively connected to the sensor to analyze the condition of the etching process detected by the sensor, and generate data representative of an analysis of the condition;

a data processor operatively connected to the analyzer so as to receive the data generated by the analyzer, configured with algorithms that process the data to determine when the etching process is to be terminated, and operative to output an end-point detection when signal when it is determined that the etching process is to be terminated; and

an interface interconnecting the data processor and the controller such that end-point detection signal when generated is transmitted to the controller.

7. The semiconductor device manufacturing apparatus according to claim 1, wherein the plasma generator comprises:

a source of the etching gas; and

a coil through which power required to excite the etching gas and thereby generate the plasma is applied.

8. The semiconductor device manufacturing apparatus according to claim 7, further comprising:

a pump connected to the chamber to evacuate the chamber;

a gate valve interposed between the pump and the chamber to selectively place an inlet of the pump in open communication with the interior of the chamber; and

a throttle valve connected to the chamber and operative to adjust the rate at which the chamber is evacuated, whereby the pressure in the chamber can be regulated.

9. A method for use in the manufacturing of a semiconductor device, the method comprising;

providing a first layer having an opening therein;

forming a second layer on the first layer including within the opening and at a region outside the opening, wherein the opening is not completely filled after the second layer is formed;

subsequently removing material of the second layer;

monitoring the structure at the region outside the opening as material of the second layer is being removed, and generating in real time data representative of the structure;

terminating the process of removing material of the second layer based on the data when the data reveals that a layer disposed under the second layer at the region outside the opening is being removed by the process; and

subsequently forming a third layer on the second layer to complete a burying of the opening.

10. The method according to claim 9, wherein the monitoring of the structure comprises sensing light reflecting from the structure, and the generating of data comprises generating data representative of the wavelength of light reflecting from an upper surface of the structure.

11. The method according to claim 9, wherein the monitoring of the structure comprises sensing gas emitted from the structure, and the generating of data comprises generating data representative of at least one component of the gas.

12. The method according to claim 9, wherein the removing material of the second layer comprises a plasma etching process.

13. A method of manufacturing a semiconductor device comprising:

providing a substrate having a trench therein,

sequentially forming a trench oxide layer and a trench nitride layer on the substrate including over sidewalls thereof that define sides of the trench and at a region outside the trench;

subsequently forming a first oxide layer on the substrate including on the trench nitride layer in the trench and at the region outside the trench, and wherein the trench is not completely filled after the first oxide layer is formed;

etching the first oxide layer;

monitoring the structure at the region outside the trench as the first oxide layer is being etched, and generating in real time data representative of the layer that is being etched;

terminating the etching of the first oxide layer when the data reveals that the trench nitride layer is being etched at the region outside the trench;

forming a second oxide layer on the first oxide layer including within the trench; and

subsequently planarizing the resulting structure down to the substrate to form an isolation layer that buries the trench, wherein the isolation layer is constituted by the first and second oxide layers.

14. The method according to claim 13, wherein the monitoring of the structure comprises sensing light reflecting from the structure, and the generating of data comprises generating data representative of the wavelength of light reflecting from an upper surface of the structure.

15. The method according to claim 13, wherein the monitoring of the structure comprises sensing gas emitted from the structure, and the generating of data comprises generating data representative of at least one component of the gas.

16. The method according to claim 13, wherein the etching is a plasma etching process using a fluorine-based gas as an etch gas.

17. The method according to claim 13, wherein at least one of the first and second oxide layers is a high density of plasma oxide layer.