Method of creating a predefined internal pressure within a cavity of a semiconductor device
View Patent ↗A method of creating a predefined internal pressure within a cavity of a semiconductor device, the method including providing the semiconductor device, the semiconductor device including a semiconductor oxide area which is continuously arranged between the cavity of the semiconductor device and an external surface of the semiconductor device, exposing the semiconductor device to an ambient atmosphere with a noble gas at a first temperature for a predetermined time period, and setting a second temperature, which is different from the first, after the predetermined time period has expired, the semiconductor oxide area exhibiting a higher permeability for the noble gas at the first temperature than at the second temperature.
1. A method of creating a predefined internal pressure within a cavity of a semiconductor device, the method comprising:
providing the semiconductor device, the semiconductor device comprising a semiconductor oxide area which is continuously arranged between the cavity of the semiconductor device and an external surface of the semiconductor device;
exposing the semiconductor device to an ambient atmosphere with a noble gas at a first temperature for a predetermined time period; and
setting a second temperature, which is different from the first, after the predetermined time period has expired,
the semiconductor oxide area exhibiting a higher permeability for the noble gas at the first temperature than at the second temperature,
the step of exposing being performed such that the noble gas is neon.
2. The method as claimed in claim 1 , wherein the step of exposing the semiconductor device to the ambient atmosphere comprises the following substeps:
setting a predetermined ambient pressure and a predetermined ambient temperature within the ambient atmosphere for the predetermined time period.
3. A method as claimed in claim 2 , wherein the step of setting the ambient pressure and the ambient temperature is performed such that the predetermined ambient pressure ranges from 2 bar to 20 bar.
4. The method as claimed in claim 2 , wherein the step of setting the ambient pressure and the ambient temperature is performed such that the predetermined ambient temperature ranges from 200° C. to 700° C.
5. The method as claimed in claim 2 , wherein the step of setting the ambient pressure and the ambient temperature is performed such that the predetermined ambient temperature ranges from 300° C. to 400° C.
6. The method as claimed in claim 1 , wherein the step of exposing is performed such that the predetermined time duration ranges from 20 minutes to 20 hours.
7. The method as claimed in claim 1 , wherein the step of exposing is performed such that the predetermined time period ranges from 20 to 240 minutes.
8. The method as claimed in claim 1 , wherein the step of providing is performed such that the semiconductor oxide area comprises silicon dioxide.
9. The method as claimed in claim 1 , wherein the noble gas, a semiconductor oxide of the semiconductor oxide area, and the first and second temperatures are selected such that the permeability for the noble gas is higher by a factor ranging from 500 to 50,000 at the first temperature than at the second temperature.
10. The method as claimed in claim 1 , wherein the step of exposing is performed such that the predefined internal pressure ranges from 0.01 Pa to 100.
11. The method as claimed in claim 1 , wherein the step of providing comprises providing an arrangement of several semiconductor devices on a wafer, and the steps of exposing and setting the temperature for all semiconductor devices are jointly performed.
12. The method as claimed in claim 1 , wherein the step of providing is performed such that prior to the step of exposing, a pressure within the cavity is lower than the predetermined internal pressure.
13. The method as claimed in claim 1 , wherein the step of providing comprises arranging a getter material within the cavity for, during activation, absorbing a different gas than the noble gas within the ambient atmosphere, the step of exposing being performed at least such that the getter material is activated.
14. The method as claimed in claim 1 , wherein the providing is performed such that the semiconductor device comprises a micromechanical device.
15. The method as claimed in claim 1 , wherein the providing is performed such that the semiconductor device comprises a microresonator or a vibrating gyroscope.
16. The method as claimed in claim 1 , wherein the step of setting is performed such that the temperature ranges from −50° C. to 130° C. after the predetermined time period has expired.
17. The method as claimed in claim 1 , wherein the step of setting is performed such that after the predetermined time period has expired, the temperature lies within a range which corresponds to the target application temperature range of the semiconductor device.
18. The method as claimed in claim 1 , wherein the step of setting further comprises setting an ambient pressure to range from 0.9 bar to 1.2 bar.