Photoresist degassing monitoring system and method

Abstract

The invention discloses a photoresist degassing monitoring system and method.The photoresist degassing monitoring system comprises a photoetching developing device and a sensor system, the photoetching developing device comprises a photoetching machine and a developing machine, a wafer placing platform and an optical element are arranged in the photoetching machine, a wafer back-baking hot plate is arranged in the developing machine, and a wafer back-baking hot plate is arranged in the developing machine; the wafer placing platform and the wafer rear baking plate are used for placing a wafer coated with photoresist; the sensor system comprises a first sensor module, a second sensor module and a third sensor module which are connected with a controller, and the first sensor module comprises at least one first crystal diaphragm thickness measuring sensor arranged at the position of an optical element. The second sensor module comprises at least one second crystal vibrating diaphragm thickness measuring sensor arranged on the wafer placing platform; and the third sensor module comprises at least one third crystal vibrating diaphragm thickness measuring sensor arranged on the wafer rear heating plate. The photoresist degassing concentration in the photoetching process can be monitored in real time, and the light source efficiency and the pattern transfer quality are improved.

Description

Technical Field

[0001] The present invention belongs to the field of microelectronic manufacturing, and particularly relates to a photoresist degassing monitoring system and method. Background Art

[0002] Deep ultraviolet (248, 193 nm light sources) exposure technology and extreme ultraviolet exposure technology widely use chemically amplified photoresists (CARs). During the exposure process, the photo acid generator (PAG) in the photoresist undergoes a photochemical reaction to remove the protecting agent and generate acid. At the same time, some by-product gases may also be released, which may include but are not limited to carbon dioxide (CO 2 ), nitrogen (N 2 ), water vapor (H 2 O), and other organic volatiles, which will affect the purity of the process environment. As a result of the decomposition of PAG or other additives, due to the photolysis of PAG and the acid evaporation during the PEB process, the photoresist will undergo a degassing reaction and generate waste gas. Any trace amount of degassing products may deposit on the optical elements, causing fogging of the exposure machine lens, resulting in a serious decline in optical performance, and affecting the light source efficiency and pattern transfer quality. Therefore, special attention needs to be paid to reducing or preventing the deposition of pollutants generated by photoresist degassing on key optical components.

[0003] The photoresist may also degas during the post-exposure bake (PEB) process. This process can promote the acid-catalyzed reaction generated during exposure. The acid acts as a catalyst during the post-exposure bake and repeats the deprotection reaction to further generate acid. During this heating process, some components in the photoresist may decompose or volatilize, resulting in degassing. If there is unevaporated solvent in the photoresist, then during the PEB process, these solvents will also volatilize and release gas. The generated waste gas may also react with the photoresist surface, resulting in distortion of the photolithographic pattern. In semiconductor lithography processes, controlling and managing the degassing problem of photoresists is very important.

[0004] In order to evaluate the degassing of photoresists during deep ultraviolet exposure, corresponding degassing analysis techniques have been developed. Existing photoresist evaluation techniques rely on gas chromatography (GC) and ion chromatography (IC) techniques, and additional chambers are required to collect degassing. Although such methods can accurately analyze the degassing components, they cannot monitor the impact of photoresist degassing on products in real time during the exposure process; while real-time monitoring of the degassing situation of photoresists is more critical for the yield of products during the production process. Summary of the Invention

[0005] In view of all or part of the deficiencies of the prior art described above, the object of the present invention is to provide a photoresist degassing monitoring system and method, which can realize real-time monitoring of the degassing concentration of photoresist in the lithography process, and improve the light source efficiency and pattern transfer quality.

[0006] To achieve the above object of the invention, the present invention provides the following technical solutions:

[0007] The present invention provides a photoresist degassing monitoring system, including a lithography and development device and a sensor system. The lithography and development device includes a lithography machine and a developer. A wafer placement platform and optical elements are provided in the lithography machine, and a wafer post-baking hot plate is provided in the developer. The wafer placement platform and the wafer post-baking hot plate are used to place wafers coated with photoresist. The sensor system includes a first sensor module, a second sensor module, and a third sensor module connected to a controller. The first sensor module includes at least one first quartz crystal film thickness measurement sensor disposed at the position where the optical elements are located. The second sensor module includes at least one second quartz crystal film thickness measurement sensor disposed on the wafer placement platform. The third sensor module includes at least one third quartz crystal film thickness measurement sensor disposed on the wafer post-baking hot plate.

[0008] The quartz crystal film thickness measurement sensor, i.e., the film thickness gauge quartz crystal system, uses a quartz crystal to monitor the film thickness in real time. This system accurately measures the film thickness by monitoring the change in the vibration frequency of the quartz crystal wafer in real time. The principle behind this is the piezoelectric resonance effect of the quartz crystal. Briefly speaking, the metal layers on both sides of the quartz crystal will generate mechanical vibrations under the action of an alternating voltage, and these vibrations will generate an alternating electric field with a very stable vibration frequency.

[0009] The present invention uses a quartz crystal film thickness measurement sensor to detect the film thickness deposited on the optical elements, the wafer placement platform, and the wafer post-baking hot plate. By calculating the film thickness, the film deposition rate can be roughly obtained, and thus the photoresist outgassing concentration can be estimated, realizing real-time monitoring of the photoresist outgassing concentration. If the estimated photoresist outgassing concentration exceeds the set concentration threshold, the lithography process can be directly paused until the photoresist outgassing concentration returns to the normal value. Some existing devices or systems for monitoring photoresist outgassing often need to collect the exhaust gas and calculate its weight, and cannot monitor the photoresist outgassing concentration in real time. The present invention effectively solves the problem that the traditional photoresist outgassing detection method cannot monitor the photoresist outgassing concentration in real time during the lithography process.

[0010] Even if some sensors are used for monitoring in existing monitoring devices, the sensors are not directly placed corresponding to the optical elements and wafers. Since the flow path of the exhaust gas cannot be accurately estimated, when the positions of the sensors do not match the optical elements and the surfaces of the wafers that really need attention, it is impossible to accurately correspond to the true impact of the detected photoresist degassing on the optical elements and wafers, which easily leads to deviation in the measurement results. The present invention aims at the impact of photoresist degassing on optical elements and wafers. Its subtle impact will cause a huge shift in process yield, rather than simply judging the cleanliness inside the lithography machine or the developing machine.

[0011] There are at least four of the second crystal oscillator film thickness measurement sensors, which are evenly distributed around the wafer on the wafer placement platform; there are at least four of the third crystal oscillator film thickness measurement sensors, which are evenly distributed around the wafer on the post-baking hot plate of the wafer. Arranging multiple crystal oscillator film thickness measurement sensors can monitor the four sides of the wafer, and through calculation, it is possible to more accurately know the impact of photoresist degassing on the photoresist on the wafer surface. If only one sensor is set, due to the non-uniformity of thin film deposition in space relative to the relatively large surface of the wafer, it will be impossible to truly reflect the actual deposition situation on the wafer surface.

[0012] The optical element is one or more lenses and / or one or more mirrors in the projection objective lens system; the first crystal oscillator film thickness measurement sensor is at the same height as the optical element, and the second and third crystal oscillator film thickness measurement sensors are at the same height as the wafer. Lenses and mirrors are key optical elements. Once a thin film is slightly deposited on their surfaces by exhaust gas, it will cause fogging of the lenses of the exposure machine, resulting in a serious decline in optical performance and directly affecting the light source efficiency and pattern transfer quality. Setting the sensors at the same height as the optical elements and wafers will improve the accuracy of the detection results.

[0013] The present invention also provides a method for monitoring photoresist degassing. A wafer coated with photoresist is placed on the wafer placement platform of the lithography machine; at least one first crystal oscillator film thickness measurement sensor is arranged at the position where the optical element of the lithography machine is located. The first crystal oscillator film thickness measurement sensor detects the thickness of the first film layer deposited on its surface, calculates the first thin film deposition rate according to the thickness of the first film layer, calculates the first photoresist degassing concentration according to the first thin film deposition rate, and if the concentration exceeds the first set threshold, the lithography process is paused until the photoresist degassing concentration in the lithography machine chamber returns to the normal value.

[0014] It also includes setting at least one second crystal oscillator film thickness measurement sensor on the wafer placement platform of the lithography machine. The second crystal oscillator film thickness measurement sensor calculates the second thin film deposition rate according to the thickness of the second film layer deposited on its surface, calculates the second photoresist outgassing concentration according to the second thin film deposition rate, and if the concentration exceeds the second set threshold, the lithography process is paused until the photoresist outgassing concentration in the lithography machine cavity returns to the normal value.

[0015] It also includes placing the wafer coated with photoresist on the post-baking hot plate of the developing machine; setting at least one third crystal oscillator film thickness measurement sensor on the post-baking hot plate of the developing machine. The third crystal oscillator film thickness measurement sensor calculates the third thin film deposition rate according to the thickness of the third film layer deposited on its surface, calculates the third photoresist outgassing concentration according to the third thin film deposition rate, and if the concentration exceeds the third set threshold, the post-baking process is paused until the photoresist outgassing concentration in the developing machine cavity returns to the normal value.

[0016] The present invention uses a crystal oscillator film thickness measurement sensor to detect the thickness of the film layer deposited on the optical element, wafer placement platform and post-baking hot plate of the wafer. By calculating the film layer thickness, the thin film deposition rate can be roughly obtained, so as to estimate the photoresist outgassing concentration, realizing real-time monitoring of photoresist outgassing. If the estimated photoresist outgassing concentration has exceeded the set concentration threshold, the lithography process can be directly paused until the photoresist outgassing concentration returns to the normal value. The present invention effectively solves the problem that the traditional photoresist outgassing detection method cannot monitor the photoresist outgassing concentration in real time during the lithography process.

[0017] The calculation formula for obtaining the thin film deposition rate by calculating the film layer thickness is: R is the thin film deposition rate, ΔThickness is the change in film layer thickness, and ΔT is the change in time.

[0018] The calculation formula for obtaining the photoresist outgassing concentration by the thin film deposition rate is: c = R × k 1 , c is the outgassing concentration, R is the thin film deposition rate, k 1 is the photoresist outgassing coefficient.

[0019] It includes the following steps:

[0020] S1: The wafer coated with photoresist enters the lithography and developing equipment, and the exposure process is carried out through the lithography machine;

[0021] S2: During the exposure process, the outgassing concentration of the first photoresist is detected by the first quartz crystal film thickness measurement sensor, and the outgassing concentration of the second photoresist is detected by the second quartz crystal film thickness measurement sensor. If the outgassing concentration of the first photoresist does not exceed the first set threshold and the outgassing concentration of the second photoresist does not exceed the second set threshold, the concentration meets the standard, and after the exposure is completed, proceed to S3; otherwise, the concentration does not meet the standard, pause the lithography process until the concentration meets the standard;

[0022] S3: Perform a post-baking process through a developing machine;

[0023] S4: During the post-baking process, the outgassing concentration of the third photoresist is detected by the third quartz crystal film thickness measurement sensor. If the outgassing concentration of the third photoresist does not exceed the third set threshold, the concentration meets the standard, and after the post-baking is completed, proceed to S5; otherwise, the concentration does not meet the standard, pause the post-baking process until the concentration meets the standard;

[0024] S5: The wafer completes the photoresist coating and developing process.

[0025] The first set threshold, the second set threshold, and the third set threshold can be the same or different and are adjusted according to process requirements.

[0026] The photoresist is a chemically amplified photoresist, and the deep ultraviolet exposure technology or extreme ultraviolet exposure technology is used in the exposure process. Chemically amplified photoresists are often used in deep ultraviolet exposure technology or extreme ultraviolet exposure technology, and chemically amplified photoresists are prone to generating by-product gases during use. The photoresist outgassing monitoring method provided by the present invention is particularly applicable to this situation. Description of the Drawings

[0027] In order to more clearly illustrate the technical solutions in the specific embodiments of the present invention, the following will briefly introduce the drawings required for description in the embodiments. Obviously, the following described drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0028] Figure 1 It is a schematic diagram of the internal part of a lithography machine in a photoresist outgassing monitoring system provided in Embodiment 1;

[0029] Figure 2 It is a schematic diagram of the internal part of a developing machine in a photoresist outgassing monitoring system provided in Embodiment 1;

[0030] Figure 3 It is a flowchart of a photoresist outgassing monitoring method provided in Embodiment 2.

[0031] Reference numerals: 1 - wafer placement platform; 2 - optical element; 3 - post - bake hot plate for wafer; 4 - wafer; 5 - first quartz crystal film thickness measurement sensor; 6 - second quartz crystal film thickness measurement sensor; 7 - third quartz crystal film thickness measurement sensor. Detailed implementation manners

[0032] The technical solutions in the specific embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0033] It should be noted that, in order to more specifically describe the technical solutions, the steps described in the following embodiments do not strictly correspond one - to - one with the steps described in the content of the invention.

[0034] Embodiment 1

[0035] A photoresist degassing monitoring system includes a lithography and development device and a sensor system. The lithography and development device includes a lithography machine and a developer. Referring to Figure 1 and Figure 2 , a wafer placement platform 1 and an optical element 2 are provided in the lithography machine, and a post - bake hot plate 3 for the wafer is provided in the developer. The wafer placement platform 1 and the post - bake hot plate 3 for the wafer are used to place the wafer 4 coated with photoresist. The sensor system includes a first sensor module, a second sensor module, and a third sensor module connected to a controller.

[0036] The first sensor module includes a first quartz crystal film thickness measurement sensor 5 disposed at the position where the optical element 2 is located. The first quartz crystal film thickness measurement sensor 5 is at the same height as the optical element 2. The optical element 2 is one or more lenses and / or one or more mirrors in the projection objective system. In this embodiment, a single lens is taken as an example. The first quartz crystal film thickness measurement sensor 5 is used to monitor the influence of photoresist degassing on the optical element 2.

[0037] The second sensor module includes four second quartz crystal film thickness measurement sensors 6 disposed on the wafer placement platform 1, evenly distributed around the wafer 4 on the wafer placement platform 1. The second quartz crystal film thickness measurement sensors 6 in the chamber of the lithography machine / exposure machine are used to monitor the thickness of the products re - deposited on the surface of the wafer 4 (the surface of the photoresist) due to photoresist degassing.

[0038] The third sensor module includes four third crystal oscillator film thickness measurement sensors 7 disposed on the post-baking hot plate 3 of the wafer, and they are evenly distributed around the wafer 4 on the post-baking hot plate 3. The third crystal oscillator film thickness measurement sensors 7 on the post-baking hot plate 3 in the coating and developing machine chamber are used to monitor the thickness of the product deposited on the surface of the wafer 4 (the surface of the photoresist) after the photoresist degasses and redeposits during the post-baking process. The second crystal oscillator film thickness measurement sensor 6 and the third crystal oscillator film thickness measurement sensor 7 are at the same height as the wafer 4.

[0039] Embodiment 2

[0040] A method for monitoring photoresist degassing uses a photoresist degassing monitoring system provided in Embodiment 1, and employs three groups of sensor modules, including a first crystal oscillator film thickness measurement sensor 5, a second crystal oscillator film thickness measurement sensor 6, and a third crystal oscillator film thickness measurement sensor 7. In other embodiments, a single crystal oscillator film thickness measurement sensor can also be provided. The wafer 4 coated with photoresist is placed on the wafer placement platform 1 of the lithography machine; a first crystal oscillator film thickness measurement sensor 5 is disposed at the position where the optical element 2 of the lithography machine is located. The first crystal oscillator film thickness measurement sensor 5 calculates the first thin film deposition rate based on the thickness of the first film layer deposited on its surface, and calculates the first photoresist degassing concentration (estimated real-time degassing concentration) based on the first thin film deposition rate. If the concentration exceeds the first set threshold, the lithography process is paused until the photoresist degassing concentration in the lithography machine chamber returns to the normal value.

[0041] It further includes setting four second crystal oscillator film thickness measurement sensors 6 on the wafer placement platform 1 of the lithography machine. The second crystal oscillator film thickness measurement sensors 6 calculate the second thin film deposition rate based on the thickness of the second film layer deposited on their surfaces, and calculate the second photoresist degassing concentration (estimated real-time degassing concentration) based on the second thin film deposition rate. If the concentration exceeds the second set threshold, the lithography process is paused until the photoresist degassing concentration in the lithography machine chamber returns to the normal value.

[0042] It further includes placing the wafer 4 coated with photoresist on the post-baking hot plate 3 of the developing machine; setting four third crystal oscillator film thickness measurement sensors 7 on the post-baking hot plate 3 of the developing machine. The third crystal oscillator film thickness measurement sensors 7 calculate the third thin film deposition rate based on the thickness of the third film layer deposited on their surfaces, and calculate the third photoresist degassing concentration (estimated real-time degassing concentration) based on the third thin film deposition rate. If the concentration exceeds the third set threshold, the post-baking process is paused until the photoresist degassing concentration in the developing machine chamber returns to the normal value.

[0043] In this embodiment, the first set threshold, the second set threshold, and the third set threshold can be the same, which is 10 15molecule / cm 2 。

[0044] The calculation formula for the film deposition rate obtained by calculating through the film layer thickness is: R is the film deposition rate, ΔThickness is the change in film layer thickness, and ΔT is the change in time.

[0045] The calculation formula for the outgassing concentration of the photoresist obtained by calculating through the film deposition rate is: c = R × k 1 , where c is the outgassing concentration, R is the film deposition rate, and k 1 is the outgassing coefficient of the photoresist.

[0046] Reference Figure 3 , the photoresist outgassing monitoring method provided in this embodiment includes the following steps:

[0047] S1: The wafer 4 coated with photoresist enters the photolithography and development equipment, and the exposure process is carried out by a lithography machine. The photoresist is a chemically amplified photoresist, and the deep ultraviolet exposure technology or extreme ultraviolet exposure technology is used in the exposure process;

[0048] S2: During the exposure process, the first outgassing concentration of the photoresist is detected by the first crystal oscillator film thickness measurement sensor 5, and the second outgassing concentration of the photoresist is detected by the second crystal oscillator film thickness measurement sensor 6. If the first outgassing concentration of the photoresist does not exceed the first set threshold and the second outgassing concentration of the photoresist does not exceed the second set threshold, the concentration meets the standard, and after the exposure is completed, it turns to S3; otherwise, the concentration does not meet the standard, the photolithography process is paused until the concentration meets the standard (for example, wait for 15 seconds and then continue), and the exposure process is continued to be completed;

[0049] S3: The post-baking process is carried out by a developing machine;

[0050] S4: During the post-baking process, the third outgassing concentration of the photoresist is detected by the third crystal oscillator film thickness measurement sensor 7. If the third outgassing concentration of the photoresist does not exceed the third set threshold, the concentration meets the standard, and after the post-baking is completed, it turns to S5; otherwise, the concentration does not meet the standard, the post-baking process is paused until the concentration meets the standard (for example, wait for 15 seconds and then continue), and the post-baking process is continued to be completed;

[0051] S5: The wafer 4 completes the photoresist coating and development process.

[0052] The description of the above embodiments is only used to help understand the method and core idea of the present invention. It should be noted that for those of ordinary skill in the art of this technology, without departing from the principle of the present invention, several improvements and modifications can still be made to the present invention, and these improvements and modifications also fall within the scope of the protection of the claims of the present invention.

Claims

1. A photoresist degassing monitoring system, characterized in that: The invention comprises a photolithography developing device and a sensor system, wherein the photolithography developing device comprises a photolithography machine and a developer, wherein a wafer placement platform (1) and an optical element (2) are arranged in the photolithography machine, and a wafer post-baking plate (3) is arranged in the developer, wherein the wafer placement platform (1) and the wafer post-baking plate (3) are used to place a wafer (4) coated with photoresist; the sensor system comprises a first sensor module, a second sensor module and a third sensor module connected to a controller, wherein the first sensor module comprises at least one first crystal oscillator film thickness measurement sensor (5) arranged at the position where the optical element (2) is located, the second sensor module comprises at least one second crystal oscillator film thickness measurement sensor (6) arranged on the wafer placement platform (1), and the third sensor module comprises at least one third crystal oscillator film thickness measurement sensor (7) arranged on the wafer post-baking plate (3).

2. A photoresist degassing monitoring system according to claim 1, characterized in that: The second crystal oscillator film thickness measurement sensors (6) include at least four sensors, which are evenly distributed around the wafer (4) on the wafer placement platform (1); and the third crystal oscillator film thickness measurement sensors (7) include at least four sensors, which are evenly distributed around the wafer (4) on the wafer post-baking plate (3).

3. A photoresist degassing monitoring system according to claim 1, characterized in that: The optical element (2) is one or more lenses in a projection objective system, and / or one or more reflectors; the first crystal oscillator film thickness measurement sensor (5) is located at the same height as the optical element (2), and the second crystal oscillator film thickness measurement sensor (6) and the third crystal oscillator film thickness measurement sensor (7) are located at the same height as the wafer (4).

4. A method for monitoring photoresist degassing, characterized in that: A wafer (4) coated with photoresist is placed on a wafer placement platform (1) of a photolithography machine; at least one first crystal oscillator film thickness measurement sensor (5) is arranged at a position where an optical element (2) of the photolithography machine is located; the first crystal oscillator film thickness measurement sensor (5) detects the thickness of a first film layer deposited on its surface, calculates a first film deposition rate according to the first film layer thickness, and calculates a first photoresist degassing concentration according to the first film deposition rate; if the concentration exceeds a first set threshold, the photolithography process is suspended until the photoresist degassing concentration in the photolithography machine chamber returns to a normal value.

5. A method for monitoring photoresist degassing according to claim 4, characterized in that: The invention also includes arranging at least one second crystal oscillator film thickness measurement sensor (6) on a wafer placement platform (1) of a photolithography machine, wherein the second crystal oscillator film thickness measurement sensor (6) detects the thickness of a second film layer deposited on its surface, calculates a second film deposition rate according to the second film layer thickness, and calculates a second photoresist degassing concentration according to the second film deposition rate. If the concentration exceeds a second set threshold, the photolithography process is suspended until the photoresist degassing concentration in the photolithography machine chamber returns to a normal value.

6. A method for monitoring photoresist degassing according to claim 5, characterized in that: The method also includes placing a wafer (4) coated with photoresist on a wafer post-baking plate (3) of a developer; arranging at least one third crystal oscillator film thickness measurement sensor (7) on the wafer post-baking plate (3) of the developer, wherein the third crystal oscillator film thickness measurement sensor (7) detects the thickness of a third film layer deposited on its surface, calculates a third film deposition rate according to the third film layer thickness, and calculates a third photoresist degassing concentration according to the third film deposition rate; if the concentration exceeds a third set threshold, the post-baking process is suspended until the photoresist degassing concentration in the developer chamber returns to a normal value.

7. A method for monitoring photoresist degassing according to claim 4, characterized in that: The calculation formula of thin film deposition rate is obtained by calculating the film thickness: R is the film deposition rate, ΔThickness is the change in film thickness, and ΔT is the change in time.

8. A method for monitoring photoresist degassing according to claim 4, characterized in that: The calculation formula for the photoresist degassing concentration obtained by calculating the film deposition rate is: c=R×k1, where c is the degassing concentration, R is the film deposition rate, and k1 is the photoresist degassing coefficient.

9. A method for monitoring photoresist degassing according to claim 6, characterized in that: The following steps are involved: S1: The wafer (4) coated with photoresist enters the photolithography developing equipment and undergoes an exposure process through the photolithography machine; S2: During the exposure process, the first photoresist degassing concentration is detected by a first crystal oscillator film thickness measurement sensor (5), and the second photoresist degassing concentration is detected by a second crystal oscillator film thickness measurement sensor (6); if the first photoresist degassing concentration does not exceed a first set threshold value and the second photoresist degassing concentration does not exceed a second set threshold value, the concentrations meet the standard, and the process goes to S3 after the exposure is completed; otherwise, the concentrations do not meet the standard, and the photolithography process is suspended until the concentrations meet the standard; S3: post-baking process through the developer; S4: During the post-baking process, the third photoresist degassing concentration is detected by a third crystal oscillator film thickness measurement sensor (7); if the third photoresist degassing concentration does not exceed a third set threshold value, the concentration meets the standard, and the post-baking is completed and the process is turned to S5; otherwise, the concentration does not meet the standard, and the post-baking process is suspended until the concentration meets the standard; S5: The wafer (4) completes the coating and developing process.

10. A method for monitoring photoresist degassing according to claim 9, characterized in that: The photoresist is a chemically amplified photoresist, and the exposure process adopts deep ultraviolet exposure technology or extreme ultraviolet exposure technology.

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