Table of Contents
Tools at SLAC: https://photos.app.goo.gl/uLpUdpsPU9Laigdp7
LBNL provided instructions for soldering leads to platinum heaters. Download yourself: LBNL PowerPoint Slides
Note: The dummy heaters feature a shiny side -- a Pt thin film over an oxide layer. Their back sides are bare silicon, ground finish.
The table below is most likely out of date. For the 19-0 ring, please use this document as a reference (it collects all the info on the heaters wired and measured by Valentina and Sam in Jan 2020):
https://docs.google.com/spreadsheets/d/1s-4BwTW910EQzInhqSd7pgCI3uvk52Jl/edit#gid=2064913736
Sample | Label | Dimension | Quantity | Who | Date |
Heaters single size | A19 | 21.3x20.5 | 9 | wired - Valentina | 4/14/21 |
Heaters single size | B19 | 21.3x20.5 | 9 | wired - Valentina | 4/14/21 |
Heaters quad size | C19 | 45x41 | 25 | wired - Valentina | 4/14/21 |
Heaters dummies for tests (wafer edges) | D19 | 45x41 | 20 | wired - Valentina 10 - 6 to Zhi | 4/14/21 |
Heaters quad size Heaters single size | A21 10 boxes | TBC TBC | 25 87 | Caterina Caterina | 4/14/21 4/14/21 |
Dummy Heaters Inventory (the table above is a screenshot of 3/22). The latest status is at
Heaters dimensions have been measured here:
https://drive.google.com/drive/folders/1bW_r5Phgyt8DJJ4dwmBe-TeskERc6VYQ
And again here using the CMM:
https://docs.google.com/spreadsheets/d/184nDPdVxXGeM7emri5dYKY1ca4Y5buHXP0zP1pMPt3o/edit?usp=sharing
Resistance measurement of a single quad heater:
1.9 ohms
Notebook PDF (HeaterSolderingPreparationNotebook.pdf) has the most up-to-date process information. – HH, JS, RH 2021
1. Using cobar core solder 63/37 (Sn64 Pb37) type with flux core or.... the type of solder makes too much difference.
The diameter of the wire needs to be small 0.012" to 0.020".
2. The solder wick is either Solder-Wick by Chemtroncs. Or Hex-Wick by Hexacon Electric Co.
3. Liquid flux for between the wick and silicon.
The liquid flux defines where the solder will flow. Don't get the flux anywhere you don't want solder.
4. Alcohol for cleaning the flux from the fixtures after the soldering. A wood toothpick and cotton swab is useful to rub off some of the remaining flux.
Also, rinse the remaining wick with alcohol as it contains dry flux and looks nicer when it's cleaned off.
5. Heaters
6. Fixture to hold heaters and fixtures
7. Hot plate (to achieve 220C)
8. Protective equipment
Cobar core solder 63/37 type with flux core
Solder-Wick by Chemtroncs (Left). Hex-Wick by Hexacon Electric Co.
(use photos for reference - NOTE: the "single" and "quad" modules are used interchangeably in the photos)
This step are illustrated in the photos here (for the quad modules):
and for the single modules here:
Turn on high setting.
Attach the thermal sensor to the aluminum rectangle ( below the washer)
Place the rectangle on the hot plate - make sure the wires don't bend and the electrical tape doesn't touch the aluminum.
In 10 mins check the temperature and if ~ 250 ℃ - turn the hot plate to 3.5 and let stabilize (fluctuations of ± 2 ℃)
Clean the fixture ethanol
Lightly screw in the rectangles to the fixture
Cut the solder wick into ~8cm lengths
Set initial wire positions
Place the heater in the fixture in the right orientation (using a vacuum pen?)
Tighten the screws making sure the wires are in the right position
Clean the heaters with ethanol
Check the temperature ~ 245 ℃
Using 2 pliers place the fixture with the heaters on the hot plate
Wait ~4 mins for the fixture to come to the right temperature (it smells funky and smokes a bit)
Using the <0.02” diameter solder perform the actual soldering - be careful not to over solder
Clean up [15 mins]
Pick up the fixture with 2 pliers and place on the aluminum sheet
Wait 2 mins for the fixture to cool down
Use ethanol to clean up residue (napkins and Q-tips)
Undo the screws and rectangles
Remove the heater carefully (maybe vacuum pen will help here?) Sometimes the soldering makes the heaters stick to the fixture.
Place the heater in the wax cover and measure the resistance
Clean the fixture again to get it ready for the next heater.
How to avoid over soldering? Practice?
Speckles on the heaters after soldering - What are they?
Maybe some kind of support for Thanh?
How to label the heaters to record the resistance measurements? Mark the wax paper
Spare heaters soldered at SLAC:
1st quad heater solder job:
Resistance for the spare quad heater: 3.5 ohms
Resistance - 3.4 ohms
Issues -
The wick just came off the heater without any force
same issue - Wick just came off the heater.
Why did it work this time?
Issues - during the failed tests, the reflective side placed on the bottom was scratched.
Resistance: 3.1 ohms
Resistance: 2.8 ohms
Resistance: 3.5 ohms
Resistance: To be measured
Soldering: Aidan and Sam under Thanh's supervision
Resistance: To be measured
Soldering: Aidan and Sam
Old heaters were removed from stavelets to reload for radiation tests. They are different in dimension than the previous heaters. Their resistance distribution is as follows: Stavelet_heaters_Resistance_distribution.pdf
for reference:
CAD views of Heaters and Ring:
Wiring In Series – Heaters are to be wired together in series after loading onto the Ring.
Connection for heaters on the ring: electrical circuit is given by the red and the green squares are the heaters. The red arrows are the position where the electric circuit connects to power supply