0. Table of contents. Author: Jaap Snijder

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1 Document nr. : JaaSni V01 Page nr. : 0 Author: Jaap Snijder 0. Table of contents 0. Table of contents Changes compared to previous versions Safety General Chemicals Bright Ultra Violet light Laser radiation Mercury poisoning How to shutdown stepper in case of emergency General information General Interface between User and stepper The use of the tracker ball Operation manual Stepper Agenda Login Main Menu Start-Up/Shut down (option 1) Batch Control (option 2) SECS Manager (option 8) How to start a batch Machine setup Define batch After processing Process Control Processing without alignment Focus Dose matrix (FEM) How to perform the matrix exposure How to read a matrix Energy meander How to perform a energy meander How to read the Energy meander Focus meander How to perform a Focus meander How to read the Focus meander Aborting the process Error handling during processing Rules & Regulations Instruction and test... 11

2 Document nr. : JaaSni V01 Page nr. : 1 1. Changes compared to previous versions Date Page number New version number Description /01 First version with Document number

3 Document nr. : JaaSni V01 Page nr. : 2 2. Safety 2.1 General The stepper is a machine with various hazardous parts moving and not moving. Don t open door or levers when the machine is working. 2.2 Chemicals Table 1: Chemicals that are being used in the SSEC Formula Name Dangerous He + 0.5%O2 Helium + Oxygen 0.5% No N2 Nitrogen No Detailed information about these chemicals can be found in the corresponding Material Safety Data Sheets (MSDS). 2.3 Bright Ultra Violet light UV light can damage eyes and can cause skin burns. Everyone working with the stepper should know the danger of UV light in the machine. Never look, direct or indirect, in the UV source of the Stepper. When someone is working at the UV source wear goggles which filters the UV light. In normal operation it is not possible to look into the UV-source. 2.4 Laser radiation Laser is a high bundled light with a high energy, it can damage eyes immediately. Lasers are random used in the stepper and are not always visible (ed focus laser). When the machine is opened be careful and always wear goggles. In normal operation there is no danger. 2.5 Mercury poisoning The exposure lamp is an Mercury high pressure lamp. It is possible that this lamp explodes; in this case do not open the lamp unit for at least 10 minutes. The exhaust will drain away the mercury.

4 Document nr. : JaaSni V01 Page nr. : How to shutdown stepper in case of emergency USE THIS BUTTON ONLY WHEN PEOPLE OR MACHINE ARE IN DANGER!! There are several emergency buttons on the system, recognizable by the big red button. It is allowed to press this button in case of emergency, the system will stop immediately. The machine will stop without checking the system and can cause serious damage to the stepper. 3. General information 3.1 General The stepper is a machine that works with wafers, sizes 75 mm, 100 mm, 125 mm, 150mm and 200mm. The wafers should be coated with a UV-light (365nm) sensitive coating before processing. The stepper exposes the coated wafers with certain pattern, and repeat this several times. The exposed pattern is printed on a mask also called a reticle, this reticle is placed on top of the lens that reduces the image 5 times. What the stepper exposé and how it exposes is written in a stepper job (made by the owner of the machine). After exposing the wafer is ready to develop. 3.2 Interface between User and stepper The interface between user and stepper is done with the following hardware: The operator console: Screen, Terminal, pointer (mouse tracker ball) Emergency buttons The wafer- and reticlehandling Status light showing: - Red : System error during processing batch - Yellow : Intervention operator needed during batch processing - Green : Batch is processing - No light : Batch finished or system is in stand-by Wafer handling indicators (input output) (pre)alignment monitors in operator console 3.3 The use of the tracker ball The tracker bal has the same function as the mouse in a normal pc. By rotating the ball it is possible to move the cursor on the screen. The buttons on the Tracker ball have the same function as the mouse buttons (Select, Change and Menu). The double-click function is not working on this UNIX operating system

5 Document nr. : JaaSni V01 Page nr. : 4 4. Operation manual 4.1 Stepper Agenda Before using the stepper it is important to fill in the agenda of the stepper. This agenda can be found on the clean room website. You can enter this site only when you had the safety tour and are authorized to use the clean room and stepper. 4.2 Login Under normal circumstance the login screen is shown, (see picture 2). When you are authorized you can login with your <username> and <password>. After that you enter the main menu (picture 1) 4.3 Main Menu After login, the operator main menu is visible. Only the black menu options are available for use. The gray options are for the engineer Start-Up/Shut down (option 1) This option is available for operators but not advisable to use. In this menu it is possible to shut down the system and initialize the system. In normal state the system is initialized and it is not necessary to use this Batch Control (option 2) This option is the most used option for batch processing, with this option it is possible to start a batch of wafers or to see how previous batches have been processed. To go back to the main menu press SECS Manager (option 8) This option is not available. 4.4 How to start a batch Machine setup Login in the machine from the login screen (picture 2) When logged in take the option <batch control> (2) After entering the batch control menu choose <Define batch> (1) Define batch Here you find a fill in form (picture 3) to tell the machine how you want to process your job. In this form it is VERY important to use the <ENTER>- or <APPLY> button for assigning the line. On every empty line the form expect data for processing the job. <Batch ID> : Type a logical name for your batch (required)

6 Document nr. : JaaSni V01 Page nr. : 5 <Job Name>: Push the select button under the rule name. After this a Folder structure is visible, here you can select the job name followed by <Accept> <Layer ID> : When clicking the line all layers in this job are displayed, chose the desired layer <Control Mode): W or C, W is for wafer mode and the C for Cassette mode <Batch Size>: Give the amount of Wafers or Cassettes to process. If it are wafers or cassettes is told in the <control mode> <Comment>: When a job is created an additional comment is written here. <Batch Type>: There are multiple choice possible the most used choices are explained in this manual: P => Production, in this mode you can only change the exposure dose and focus. E => Energy meander: In this mode it is possible to vary the Exposure dose in steps. (see 5.3) F => Focus meander, this mode is for vary the focus in steps. (See 5.4) M => Matrix, this mode is for varying the energy and focus in steps at the same time. (See 5.2) Under process data you will find how many images will be exposed in the selected layer. When pressing the next or previous button below this window it is possible to see all the images and their image ID. <Energy [mj/cm2]>: This displays the Standard energy for the image selected under process data. Fill in the correct energy followed with <ENTER> <Focus Offset>: This displays the standard focus to the image selected under process data. Fill in the correct focus value followed with <ENTER> The option focus tilt in X and Y are seldom used, only when the surface is tilted this is an possible option. <Illumination> It is not possible to change this but it has to be set on Default <Apply>: It is very important to press this button when you want to apply the Energy and Focus for only the selected image under Process data. When the <NEXT> or <PREVIOUS> button is pressed (next to Image), you can apply another energy and focus to the chosen image. <Preset>: when everything is filled in and this button is pressed these values are applied to all images in that layer Place Cassettes on the machine Now it is time to put the wafers on the machine, on the right side of the machine there are 4 Cassette station covers. Only the two on the right hand side are used for cassette processing, the two other places are for a wafer track option (not available). The cassette on the right side is the input cassette and on the left side the output cassette. Only use the dedicated cassettes Change/exchange Reticles in the box Reticles (masks) can only be handled on the stepper in a special box, this box can be opened with the box exchange lift. On the reticle exchange table is an empty box on a box exchange lift. Place the box with the open cassette to the front on the exchanger, the box will fall in place. Press the white button on the backside of the box, wait till the box is totally open. Take the reticle out of the box and slide it carefully into the cassette,

7 Document nr. : JaaSni V01 Page nr. : 6 Important: the chrome side faces down and the reticle prealignment marks are at the front of the cassette. When the recticle is in the cassette press the white button again and wait untill the green LED is on Change/exchange Reticlebox The stepper needs before starting the batch the correct reticle in a reticlebox. When transporting the reticlebox please support the bottom of the box. At the front top of the stepper is the position to put the box on. The opening of the cassette should point towards the stepper. The box fits one way. Do not shake tilt the box, and certainly do not apply any force!! Now the reticlebox should be latched to the stepper, this can be done in two ways: 1. On top of the batch control screen are 8 buttons. Push the button named <Mat Hdl> (material handler). Then chose option (3) exchange reticle box OR 2. Push after filling in the batch definition the <RUN> button at the bottom of the page. The stepper will check all systems, when the reticle is not there he will answer with the same screen as in option (1) On screen following after the two possibility s you will find the reticle exchange box screen (see picture 4). Half way the screen you have two buttons <Read 1> and <Unlock 1>. When there is no box or the box is placed wrong the <Read 1> button is gray, in this case please put the box on the elevator. Push the< Read1> button and wait till the stepper red the reticles (takes a while). When the reading is done all reticle id s are visible on screen. Press the <Cancel> button on top of the screen. The stepper will run the batch in case of option (2). When the first option is chosen press <Exit> button followed by the <RUN> button. 4.5 After processing After processing, the stepper a popup screen is shown with the process summary, exit this screen. Now the stepper needs to be cleared of reticle box, wafers and has to be logged out. Exchange reticle box (see ) put the box back. Take the wafer cassette from the machine. Logout from the system: Press cancel or exit till the question do you want to logout and answer this with YES. 5. Process Control In this chapter you will find the non standard processing.

8 Document nr. : JaaSni V01 Page nr. : Processing without alignment When exposure has to be done without any alignment and the job expects an alignment. The next steps should be done: Change the batch type to M Click next to Modify <Alignment> under <Batch Data> A pop-up screen appears (see picture 5) First change Optical prealignment from D (default) to N (None) Second change Alignment Type from D (Default) to Z (Zero) Click on <Accept>, you will return to the define batch screen 5.2 Focus Dose matrix (FEM) When you are not sure what energy and focus is necessary for exposing your wafers it is possible to check this on one matrix. In this matrix we can change the dose and focus at the same time. When you do not now where to start with your energy I advise to start with an Energy meander test (See 5.3) How to perform the matrix exposure Change the Batch Type from P (production) to M (Matrix) followed by <EN- TER>. Now you see a pop-up screen what is asking you, which parameter you want on the X-axis change this to Energy. For the Y-axis chose the Focus. Next to the Energy and Focus you will find the possibility to fill in a Delta value. This Delta will be added or subtracted from the value filled in at the left side of the screen How to read a matrix Normal when shooting a matrix a square matrix is exposed of 9 X 9 images (see picture) -ΔF + ΔF -ΔE Flat + ΔE

9 Document nr. : JaaSni V01 Page nr. : 8 With the standard Matrix layout the centre image is the value filled in by Energy and Focus. Every step to the right add 1 delta energy, every step away from the flat subtracts one delta Focus. 5.3 Energy meander When you do not have any clue how high the doses is for your process it is possible to perform a Energy meander test. In this case you have to be careful that the energy is not exceeding 500 mj/cm2. The energy can be higher when the outcome of the test gives no popping and the structures are ok How to perform a energy meander Change the Batch Type from P (production) to E (energy meander) Next to the Energy you will find the possibility to fill in a Delta value. This Delta energy will be added with every step How to read the Energy meander With a standard matrix of 9X9 images the meander works as follows. Start Flat The energy filled in is the start energy, every image to the right adds 1 delta to the start energy. 5.4 Focus meander This option is for checking what the focus is doing with fixed energy. This option is rarely used; normally the matrix is used when the energy is roughly known How to perform a Focus meander Change the Batch Type from P (production) to F (Focus meander) Next to the Focus you will find the possibility to fill in a Delta value. This Delta energy will be added with every step

10 Document nr. : JaaSni V01 Page nr. : How to read the Focus meander The reading is in the same way as the Energy meander. Start Flat The focus filled in is the start focus; every image to the right adds 1 delta to the start focus. 6. Aborting the process In case of a mistake it is possible to stop the system. In that case push the <STOP> button on top of the screen. The stepper will react with a popup screen asking you: 1. Ignore stop request 2. Remove wafers from stepper only 3. Remove wafers from litho cluster When option 2 is entered the stepper will remove the wafers from the system. When the machine was busy with exposing the stepper will finish the current wafer and put all the wafers back in the output cassette. 6.1 Error handling during processing Whenever there are ERRORS occurring during processing of substrates, please contact the machine owner.

11 Document nr. : JaaSni V01 Page nr. : Rules & Regulations From the side of all users, we expect from them to strictly follow the rules for using the tool. The stepper is a very sensitive exposure tool and therefore the wafers and the operators should be aware of this sensitivity. The list of old rules has been extended: 1. All wafers should wafer an EBR/BSR after coating. 2. The backside of the wafers has to be clean, no particles or dirt or resist. 3. The bow of the substrate may not exceed 100 microns. 4. When non standard resists are applied to the substrate the owner should be notified. 5. It is allowed to use SU8 on the stepper with a maximum thickness of 40 microns and applied on the dedicated spinner. 6. The operator may only use the system with his own login name. 7. The wafer etch may not be damaged. These rules cannot guarantee zero wafer breakage, but at least minimize the risk

12 Document nr. : JaaSni V01 Page nr. : Instruction and test The only person, who is allowed to carry out the instruction, is the machine owner. Normally the instruction will take about half an hour and will be given only after reading this manual. First the construction (major parts) and possibilities of the machine will be explained with respect to running different substrate sizes and using the various chemicals. After this the complete operating screen and the correct way to run a cleaning process will be explained on the basis of the Operating Manual as described in chapter 4. Subsequently the student will perform a complete sequence of setting and running the correct cleaning process based upon a substrate of its/her own, independently as a test.

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