A Thesis Presented to
the Faculty of the Alfred University
Thick Film Silver Circuit Conductor Adhesion to Vitreous Substrates by
Grant L. Baldwin
In Partial Fulfillment of the Requirements for The Alfred University Honors Program
May 2022
Under the Supervision of:
Chair: Dr. William LaCourse Committee Members:
Dr. Darren Stohr Dr. Xingwu Wang
ii
ACKNOWLEDGEMENTS
This thesis idea was originally brought to my attention by Mr. Tim LeClair, a friend who has been working in the microelectronics industry ever since graduating Alfred University. At first, I was concerned about transitioning away from ceramics and working with materials I have more limited knowledge of, but he reassured me that this thesis would help achieve a better understanding of all materials. Current industry struggles with transitioning to new substrates and this idea would further enhance the future miniaturization of microelectronics.
I cannot thank my thesis advisor, Dr. Darren Stohr, enough for being an incredible mentor throughout this entire process. A significant number of roadblocks were had but he was always reassuring that there is a solution, we just need to find it. His knowledge of this field has helped me vastly grow academically while his kindness and determination has helped me grow as a person.
Without the help of Dr. Ning, I would have not been able to secure the paste used for this research. One of these roadblocks we faced was getting our hands on silver and copper pastes and Dr. Ning was able to supply us with a silver paste.
The quartz glass obtained was directly from Dr. LaCourse which proved to be a notable part of this experiment. Thank you for providing our other substrate.
Lastly, I would like to thank my roommate and best friend, Nicodemus Rod. From being strangers to becoming best friends and everything in-between, I deeply thank him
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for giving me not only an incredible friendship but something that will be remembered for the rest of our lives. My appreciation for him has no bounds.
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TABLE OF CONTENTS
ACKNOWLEDGEMENTS………...ii
TABLE OF COTENTS………..iv
LIST OF TABLES………...v
LIST OF FIGURES………vi
ABSTRACT………..vii
INTRODUCTION………...1
EXPERIMENTAL PROCEDURE……….6
RESULTS……….12
DISCUSSION………...16
CONCLUSION……….19
FUTURE WORK………..20
REFERENCES………..21
APPENDIX………...22
v
LIST OF TABLES
Table I. CTE of materials being used throughout experiment……….4
Table II. Determination of sputter coating parameters using three sample sets at varying pressure………7
Table III. Pre-adhesion resistance averages of all sample sets. ……….12
Table IV. Post-adhesion resistance averages of all sample sets. ………..12
Table V. Average pre-resistivity (before adhesion testing) values. ………13
Table VI. Average post-resistivity (after adhesion testing) values. ………...13
Table VII. Resistance testing one week apart to determine if oxidation is occurring for age testing purposes. ………14
Table A-1. Measurements of samples for resistivity calculations. ………...22
Table A-2. Pre-adhesion resistance data. ………..24
Table A-3. Post-adhesion resistance data. ………26
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LIST OF FIGURES
Figure 1. Sputter coating settings used for experiments using the Cressington Sputter Coater. ……….7 Figure 2. Firing cycle for DuPont 7095 silver conductor paste used during experiments. .9 Figure 3. Example of copper tape placed on edges of substrate to create pads for
resistance measurements. ………..10 Figure 4. Example of packing tape applied to substrate for adhesion testing. …………..11 Figure 5. Silicon substrate with silver paste applied in serpentine pattern. ………..14 Figure 6. Sample 6E, quartz glass substrate with silver paste, showing failure of glass. .15 Figure 7. Resistivity Comparison between vitreous substrates and their respective silver sputter coating and/or paste test. ………...16 Figure 8. Crack propagation occurring due to thermal stress between paste and
borosilicate glass substrate. ………...18
vii ABSTRACT
Alumina (Al2O3) is currently the industry standard substrate for thick film circuit conductors. Recently developed high speed/precision femto-second lasers can fabricate fine diameter thru-vias on fine pitches in glasses and fused silica. Thru-via interconnects with these miniaturized dimensions are not possible using alumina substrates. Miniaturized glass thru-via substrates needed for mobile communication products (next Gen cellphones) require high conductivity metallic circuit traces that are well bonded to the glasses. The conductors were assessed by comparison for resistivity shifts and tested for mechanical adhesion variation. Sputter coating of silver onto borosilicate slides through various intensities was done to determine adhesion capabilities as well as baseline resistivity measurements. Application of silver paste onto both borosilicate and quartz glass was attempted to determine adhesion and resistivity values. Various methods of attaining adhesion to the glasses was explored such as, painting of paste, sputter coating foundation, and a combination of the two. The sputter coating offered lower resistivity values and as good as adhesion while the silver paste displayed higher resistivity values due to less silver content in paste and thermal stress issues leading to cracking. The microelectronics industry is challenged with the development of copper (Cu) and silver (Ag) adhesion to vitreous glasses and fused silica. Thick film circuits are used in almost all electronic industry applications and would benefit from these discussed technical improvements.
INTRODUCTION A. Transitioning to Vitreous Substrates
Vitreous substrates become more applicable to the microelectronic industry with the introduction of short-pulsed femtosecond lasers that are capable of extremely high precision energy deposition at specific locations [1]. New approaches are being developed to create adhesion exceeding that of current industry standards with these new vitreous substrates. In this study, experimentation of three new techniques will take place on two vitreous substrates.
B. Metal on Glass Adhesion
Traditionally, chemical adhesion through the usage of frit within the paste is used to create adhesion between the substrate and paste. This research both challenges and expands this approach by using both mechanical and chemical bonding techniques. Two vitreous substrates were deemed to be required: borosilicate and quartz glass. Borosilicate glass being typically composed of 70-80 wt% SiO2 and quartz glass being 100 wt% SiO2
[2]. Three different techniques of achieving adhesion between the substrates and metal was employed: Sputter coating for mechanical bonding, silver paste for chemical bonding, and a mixture of the two.
to island formations once the current is slowed down in the sputter coating process.
The idea behind sputter coating a sample for the purpose of adhesion and resistivity testing is quite simple. A vacuum is pulled within the chamber where the sample is placed
2
and then filled with argon (Ar). The argon acts as an inert gas and allows for the creation of a magnetic electric field. This magnetic electric field then allows for argon plasma to be formed which knocks atoms and ions off the sputter target. By controlling the current, the acceleration of the ions can be increased or decreased. Increasing the current/potential accelerates the particles towards the surface creating penetration sites thus a physical adhesion. This increase in potential creates more and better nucleation sites which are then used by the atoms for a strong bond to the penetrated ions. The main concern with this approach is a low-density layer thus why decreasing the potential of the ions creates a uniform layer. The increase in argon content was due to worries about oxidation of the silver layer as having oxygen in the environment would lead to this.
Chemical bonding can be directly controlled based on the frit composition as well as percentage of paste composed of the frit. The DuPont 7095 paste being used for this experiment contains 65% silver and 35% frit allowing for high adhesion capabilities [3].
Standard industry screen printing pastes contain between 2-5% glass frit [4]. This discrepancy in silver and frit content in this experiment will have a direct result on the data.
A higher frit content will allow for greater chemical bonding thus better adhesion while a higher silver content will achieve greater resistivity values. Using a 2-5% frit content means lower adhesion but much greater resistivity compared to the 35% frit content used in this study. The composition of the frit for this experiment is unknown.
A combination of the two techniques, sputter coating and paste, would allow for both mechanical and chemical bonding to occur. As stated before, the sputter coating layer would provide a mechanical bonding layer using purely metal particles thus would achieve
3
maximum resistivity values. The paste applied directly to the sputter coating layer would provide two chemical bonding layers, the ions within the sputter coating layer interacting with the ions in the paste, and the frit chemically bonding to the substrate.
C. DuPont 7095 Circuit Conductor Paste and Sputter Coating
Sputter coating is a process in which the surface of a sample is coated with a material capable of carrying electrons. Traditionally used for SEM imaging here at Alfred University, the decision to use it as a way for mechanical adhesion between a metal and vitreous substrate for the purpose of bonding and resistivity testing was unique. To achieve this, a space containing the desired sample is enclosed with the desired metal targetter directly above. A vacuum is pulled in the enclosed space removing the inside atmosphere.
Once this is complete, the enclosed space is refilled with Argon (Ar) which acts as a suitable inert gas for the transfer of ions between the cathode and anode. The operating pressure inside the enclosed space as well as the current flow can be altered. Changing the amount of current directly affects the deposition rate of the metal targetter to the surface of the sample. It is important to remember that you are taking away material from one source (targetter) and applying it to another. Overtime, this will result in the complete degradation of the targetter.
The DuPont 7095 paste was provided by Dr. Ning, a professor at Alfred University.
This paste contains 65% silver and provides the benefit of being able to fire at a lower temperature with high adhesion [3]. This was desired as one of the two vitreous substrates being used, borosilicate glass cannot go to high temperatures without deforming or even
4
melting. Quartz glass does not face the same issue as the borosilicate glass enabling an even higher temperature if desired.
D. Thermal Stress
The major concern for microelectronics is directly related to their temperature. For every 2°C increase, the reliability of a silicon chip decreases by roughly 10%. “The major cause of an electronic chip failure is due to temperature rise (55%) as against other factors which accounts 20% vibration, 19% humidity, and 6% dust.” [5] Working with electronics also means working directly with their heat output which directly impacts their longevity and stresses encountered. “To reduce thermal stress or eliminate thermal failure requires both a selection of the proper materials and a minimization of the temperature changes through thermal management…” [5]. The further miniaturization of microelectronics a drastic rise in thermal issues.
Table I. CTE of materials being used throughout experiment.
Material Coefficient of Thermal Expansion (10-6 /°C)
Alumina 10.3 * 10-6 /°C
Borosilicate Glass 5 * 10-6 /°C
Quartz Glass 5 * 10-7 /°C
Silver 18.8 * 10-6 /°C
Copper 16.7 * 10-6 /°C
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E. Current Industry Process for Creation of Silicon Substrates
Traditionally, silicon is used as the substrate for any microelectronic device as it acts as a semiconductor. Silicon can be altered however needed to fit the needs of the device it is being used for. Although silicon is an extremely abundant resource, it is often found bonded to other impurities not suitable for microelectronic production. Pure silicon needs to be used as the substrate otherwise the impurities will dampen the efficiency of the microelectronic. The creation of pure silicon is done by melting the impure sand silicon and carbon. This results in the creation of 99% pure silicon with the byproduct being carbon monoxide. Further processing is done to the silicon which takes it from 99% to 99.999%
pure silicon because as mentioned before, impurities will ruin the efficiency of the microchip. In the end, a large cylindrical pure silicon ingot is created allowing for the slicing of thin layers to be used as the substrate in the microchip process. These wafers can be easily changed in diameter and thickness depending on the desired outcome [8].
6
EXPERIMENTAL PROCEDURE A. Sputter Coating Preparations
Fine tuning of the sputter coating parameters was initially completed with the creation of three sample sets of borosilicate glass each containing three samples within each set. These samples were created by using borosilicate glass microscope slides which were then cut in half to approximately 3.75mm in length. This was necessary to fit each sample within the Cressington Sputter Coater sample holder. Masking and/or packing tape was used to create a thin strip on the surface of the samples, effectively protecting the rest of the glass from becoming sputter coated.
B. Sputter Coating Settings
Acceleration of the particles was deemed to be of utmost importance as creating embedded particles into the surface of the glass substrate would allow for mechanical adhesion between the silver particles and the vitreous substrate. Several different attempts were made in the creation of a sputter coating that allowed for both adhesion and a thickness large enough for measurements and future adhesion to silver paste to be used.
Table 1 showcases the attempts made into finding an optimal solution to this problem.
Sample set 3 proved to provide both the best silver layer overall compared to sample sets 1 and 2. For ever sample set created requiring a sputter coating layer, the sputter coating settings from sample set 3 was used. Thickness of the sputter coating sample was determined from prior work completed at Alfred University. This thickness was
7
approximately 12nm which was used for all calculations involving a sputter coated layer [7].
Table II. Determination of sputter coating parameters using three sample sets at varying pressure.
Sample Sets
1st Current (mA)
1st Pressure (mb)
1st Time (secs)
2nd Current (mA)
2nd Pressure (mb)
2nd Time (secs)
1 30 0.08 30 10 0.08 120
2 30 0.08 30 10 0.1 120
3 30 0.12 30 10 0.12 120
Figure 1. Sputter coating settings used for sample set 3 using the Cressington Sputter Coater.
C. Application and Firing of Silver Paste
All sample sets that required application of silver paste to the vitreous substrate did not have a varying procedure. DuPont 7095 silver conductor paste, containing 65% silver, was used for every sample set. Application of the paste was done by using two pieces of quartz glass with a determined thickness at the appropriate width on the substrate. Another piece of quartz glass was then used to scrap all excess paste off creating a uniform surface
8
which was consistent across all sample sets. The appropriate width was predetermined by tape placement and varied from sample to sample thus was nonuniform.
The DuPont 7095 paste required a drying period of 15 minutes at 150°C and then firing at 540-590°C at peak. Timing for the peak temperature could be adjusted based on optimization of the composition of the substrate. The peak temperature used was at 500°C and to be held for 30 minutes as shown in Figure 1. During the firing cycle, the 15-minute drying time was included at 150°C. All increments of increasing temperature was at 5°C per minute with the cooling rate roughly 2.5-3°C per minute. The total firing process took roughly six hours from start to finish.
Figure 2. Firing cycle for DuPont 7095 silver conductor paste used during experiments.
25
150 150
500 500
25 0
100 200 300 400 500 600
0 50 100 150 200 250 300 350 400
Temperature (°C)
Time (Minutes)
Firing Cycle
9 D. Testing Resistivity and Adhesion
A two-point probe resistance measurement was collected by using an ohmmeter. It was quickly discovered that the sharp points of the probe would scratch away the thin layer of the silver sputter coating layer thus not giving accurate measurement readings. To overcome this, copper tape was placed on the ends of the substrate. This process worked due to the resistivity of copper being less than that of silver.
Figure 3. Example of copper tape placed on edges of substrate to create pads for resistance measurements.
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Adhesion of all sample sets was tested by using packing tape as a form of applying load to the silver sputter coating and/or silver paste. Determination of the load was done by placing a small sliver of tape on a scale and measuring the load in grams required to peel the tape from the scale. This number came out to be 450g which was then used to back calculate the force.
Figure 4. Example of packing tape applied to substrate for adhesion testing.
11 RESULTS
Resistance measurements were used for calculating resistivity of the silver sputter coating, silver paste, and the two combined. Resistance values were taken pre-adhesion testing as well as post-adhesion testing for determining if silver was lost upon the adhesion testing process. Pre- and post-adhesion resistance values can also be seen in Table A-2 and A-3 in the Appendix, respectively.
Table III. Pre-adhesion resistance averages of all sample sets.
Sample Set Average Resistance (Ω)
3D-H 39.3
6A-F 8.5
7A-F 40.7
8A-F 3.7
9A-F 0.4
10A-F 0.4
Table IV. Post-adhesion resistance averages of all sample sets.
Sample Set Average Resistance (Ω)
3D-H 29.3
6A-F 0.4
7A-F 41.0
8A-F 0.4
9A-F 0.4
10A-F 0.4
12 Using equation 1,
𝜌𝜌=𝑅𝑅 ∗ �𝐴𝐴
𝐿𝐿� (1)
the values for resistivity can be calculated using the resistance values previously gathered as well as the cross-sectional area and length measurements of the sample. The data used in this equation can be found in Table A-1.
Table V. Average pre-resistivity (before adhesion testing) values.
Sample Set Average Resistivity (Ω*m) Standard Deviation (Ω*m)
3D-H 5.34E-09 6.12E-10
6A-F 2.10E-04 5.07E-05
7A-F 5.88E-08 4.45E-09
8A-F 7.33E-05 1.41E-05
9A-F 9.20E-06 9.15E-07
10A-F 1.04E-05 2.39E-06
Table VI. Average post-resistivity (after adhesion testing) values.
Sample Set Average Resistivity (Ω*m) Standard Deviation (Ω*m)
3D-H 3.99E-09 2.33E-10
6A-F 9.79E-06 1.15E-06
7A-F 5.95E-08 6.20E-09
8A-F 7.90E-06 3.06E-07
9A-F 9.20E-07 9.15E-07
10A-F 1.04E-05 2.39E-06
Additionally, it was discovered that there was a possibility of oxidation over time leading to an experimentation of age testing samples. Only sample 3C and 3D were used for this experiment to determine if the sputter coating was oxidizing over time.
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Table VII. Resistance testing one week apart to determine if oxidation is occurring for age testing purposes.
Sample Pre-Resistance Average (Ω) Post-Resistance Average (Ω)
3C 72 68
3D 83 71
The maximum force applied to each sample during adhesion testing used Equation 2,
𝑃𝑃 = 𝐹𝐹 𝐴𝐴
(2) which resulted in finding a value of 13.4kPa. All sample sets were able to withstand this load applied directly to the sputter coating and/or silver paste.
To meet industry standards, resistivity testing was completed on an industry serpentine screen-printed silver paste onto a silicon substrate. It maintained a value of exactly 7Ω for every resistance test giving a resistivity value of 1.98∗10−5.
Figure 5. Silicon substrate with silver paste applied in serpentine pattern.
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Failure of a quartz substrate sample did occur due to dropping of a sample before the firing cycle. The sample went through the firing cycle to allow for visual inspection of adhesion post firing. After firing, the silver paste peeled creating an arc like shape away from the quartz glass. As can be seen in Figure 6, the paste itself was accompanied by the quartz glass during the separation process.
Figure 6. Sample 6E, quartz glass substrate with silver paste, showing failure of glass.
Careful inspection of the rest of the samples for cracking or signs of thermal stress was done when sample 6E showcased failure. Upon inspection, it was determined that thermal stress cracking for all paste samples can be observed. Samples containing the sputter coating layer did not influence the cracking caused by the paste.
15 DISCUSSION
For a successfully experiment, it was determined that silver needed to adhere to the surface of the vitreous substrate as well as provide a resistivity value similar to that of the industry sample on silicon. For comparison purposes, the resistivity value of pure silver is 1.59∗10−8 𝛺𝛺 ∗ 𝑚𝑚. The values for the sample sets can be seen in Tables 4 and 5 with Figure 7 showcasing the comparison of each sample sets average resistivity.
Figure 7. Resistivity Comparison between vitreous substrates and their respective silver sputter coating and/or paste test.
Borosilicate glass with sputter coating (BSG-S), quartz glass with sputter coating (QG-S), borosilicate glass with paste (BSG-P), and borosilicate glass with both sputter coating and paste (BSG-S+P) performed better than the industry standard sample on silicon. Quartz glass with paste (QG-P), and quartz glass with sputter coating and paste
0 0.00005 0.0001 0.00015 0.0002 0.00025
0 1 2 3 4 5 6 7
Re sis tivi ty (ohm *m )
Sample
Resistivity Comparison
BSG - S QG - S BSG - P QG - P BSG - S + P QG - S + P Industry on Si
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(QG-S+P) did not perform better than the industry standard sample on silicon. It appears that the borosilicate glass substrate was overall better than the quartz glass substrate as the borosilicate glass samples were able to give better resistivity values than that of the industry standard on silicon. The substrate themselves should not have an impact on the resistivity values, but it may play an important role in the adhesion which would affect the resistivity values given.
The quartz glass samples containing the silver paste were potentially underfired leading to the stark difference in resistivity values. The quartz samples were fired together separately from the borosilicate glass samples potentially leading to this error. However, even with these being underfired, the resistivity values should be similar leading to several hypotheses on why this has occurred. Glasses can show ionic conductivity at elevated temperatures. This is highly unlikely but a significant problem if it has occurred. The silver may be more chemically active in quartz as some silver may be incorporated into the glass network leading to an increase in resistivity thus a higher value for quartz. Overall, the sputter coating layer itself has the best resistivity due to its lack of frit and pure silver content compared to the silver paste.
As shown in Tables 4 and 5, pre- and post-adhesion testing resulted in varying results per sample set. If silver material is removed, it will equate to a smaller resistivity value in response. After doing the adhesion testing, it was data shows no or limited changes in resistivity values indicating that no silver was removed from the substrate. Overall, every sample passed the adhesion testing.
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The creation of a mechanical bonding layer on the surface of the substrate by accelerating particles fast enough in the sputter coater to embed them into the surface proved to provide adhesion as well as resistivity values competing with the industry standard on silicon sample. The chemical bonding between paste and substrate by means of frit within the paste worked exceptionally well for the borosilicate glass but not for the quartz glass. This could be due to the composition of the frit within the paste not interacting as well with quartz glass compared to the borosilicate glass. The mixture of mechanical and chemical bonding proved to not have an affect on adhesion compared to the other sample sets. The resistivity of the mixture on borosilicate glass was once again competing with the industry standard on silicon but the quartz class samples were unable to.
After conducting the resistance testing, it was noticed that the ohmmeter being used for testing could not read values below 0.4Ω. This resulted in skewed data but can be used as the maximum possible resistivity value instead of an exact value.
Thermal stress issues were prevalent throughout the samples. Both glass substrates would crack underneath the paste where it was bonded to the glass. This can be seen in Figure 8, where the crack propagated far enough to snap the slide in half. These issues only occurred in samples using the paste therefore it is believed that during the firing cycle, the chemical bonding that occurs creates enough thermal stress on the glass for it to crack.
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Figure 8. Crack propagation occurring due to thermal stress between paste and borosilicate glass substrate.
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CONCLUSIONS
This thesis was designed for challenging the current industry standard substrates by using vitreous materials for microelectronics. Both borosilicate glass and quartz glass proved to be exceptional substrates for microelectronics. Sputter coating resulted in fantastic adhesion capabilities as well as providing 100% pure silver on the surface giving a resistivity value close to pure silver. The silver paste proved to also give adhesion capabilities greater than expected through the means of chemical bonding. However, the paste contained only 65% silver with the rest being frit to get the adhesion. Due to this, compared to the sputter coating, the resistivity values suffered. Thermal stresses were found in both glasses as cracks could be visibly seen between the paste and glass. Due to the coefficient of thermal expansion (CTE) of quartz glass being extremely low, it cannot match the CTE of silver leading to a thermal expansion incompatibility. All samples using the silver paste were fired in an air environment which allows for plenty of oxygen for oxidation to occur. This may explain why there is orders of magnitude difference between quartz and borosilicate samples resistivity values. Now that it is known that adhesion is possible on these vitreous substrates, fine-tuning of the sputter coating settings and the components of the paste can be completed.
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FUTURE WORK
Due to the limited capabilities here at Alfred University, basic pattern shapes had to be used. Complex sputter coating patterns to better resemble microelectronic chips, or the serpentine pattern as shown before, would be ideal. The usage of an actual screen printer to get the desired designs would create data better than what is being presented.
Resistance measurements not being able to go below 0.4 hinder the overall results of this experiment thus an ohmmeter better capable would better fit this work.
Fine tuning of the firing cycle of the paste based on composition would create better samples for testing. At the peak temperature fired, the samples were technically underfired.
Dr. LaCourse and Dr. Stohr wanted to introduce a third substrate, recycled glass.
Cheaper than all the others, if a viable solution for adhesion could be found for recycled glass while maintaining resistivity, it may be a future path microelectronics take. This idea was not implemented due to the forming process of recycled glass not meeting our standards for this experimentation at the moment. Composition of the recycled glass would alter per batch which could prove to be difficult to work with when applying a paste with a specific frit content.
21 WORK CITED
[1] Varkentina, Nadezda, et al. “Examination of Femtosecond Laser Matter Interaction in Multipulse Regime for Surface Nanopatterning of Vitreous Substrates.” Optics Express, vol. 21, no. 24, 2013, p. 29090.
[2] Hasanuzzaman, M., et al. “Properties of Glass Materials.” Reference Module in Materials Science and Materials Engineering, 2016.
[3] DuPont. “DuPont 7095 Silver Conductor.” Technical Data Sheet.
[4] Olweya, S. “Fine-Line Silver Pastes for Seed Layer Screen Printing with Varied Glass Content.” Energy Procedia, vol. 43, 2013, pp. 37–43.
[5] BĂJENESCU, Titu-Marius. “Miniaturisation of Electronic Components and the Problem of Device Overheating.” Electrotehnica, Electronica, Automatica, vol. 69, no. 2, 2021, pp. 53–58.
[6] “Electron Microscopy Sciences.” Sputter Coater Principles Technical Data Sheet.
[7] Guariglia, Amanda B. “Measuring Sputtered Metallic Coating Thickness and Density.” Alfred University, n.d..
[8] Papadopoulos, Loukia. “How the Chips Found in All Our Electronics Are Manufactured.” Interesting Engineering, 4 Jan. 2022.
22 APPENDIX
Table A-1. Measurements of samples for resistivity calculations.
Sample Length (nm) Average Width (nm) Thickness (nm)
3A 18338800 215000 12
3B 18643600 213000 12
3C 19329400 216000 12
3D 19151600 226500 12
3E 18440400 195000 12
6A 36620000 7700000 140000
6B 36150000 6035000 140000
6C 36460000 6230000 140000
6D 36670000 5410000 140000
6E 30450000 5440000 140000
7A 38820000 4135000 12
7B 40000000 5365000 12
7C 40310000 5255000 12
7D 37750000 4670000 12
7E 40250000 4460000 12
8A 35850000 5245000 140000
8B 36740000 5385000 140000
8C 38570000 5285000 140000
23
8D 38520000 5110000 140000
8E 38710000 5540000 140000
9A 38060000 6320000 140000
9B 37300000 6780000 140000
9C 37770000 6665000 140000
9D 37510000 6080000 140000
9E 38070000 5130000 140000
10A 37280000 8215000 140000
10B 37320000 6110000 140000
10C 38280000 6195000 140000
10D 37920000 5050000 140000
10E 37430000 9345000 140000
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Table A-2. Pre-adhesion resistance data.
Sample Test 1 Test 2 Test 3 Test 4 Test 5 Average
Borosilicate Glass - Sputter Coating w/
Copper Tape as "Pads"
3D 32 33 31 32 31 31.8
3E 43 48 46 51 40 45.6
3F 43 43 41 36 38 40.2
3G 45 43 35 39 38 40
3H 36 40 38 37 43 38.8
Avg. 39.28
Quartz Glass - Paste Only
6A 8.3 8.4 7.1 8.3 7.8 7.98
6B 7.1 7.9 7 6.7 6.9 7.12
6C 11 11.4 10.7 11.3 10.3 10.94
6D 7.2 5.8 6.8 6.3 6.4 6.5
6E 9.7 10.3 11.1 9.3 10.4 10.16
Avg. 8.54
Quartz Glass - Sputter Only
7A 45 47 44 48 49 46.6
7B 39 39 38 41 43 40
7C 47 41 37 36 39 40
7D 37 37 32 35 36 35.4
7E 44 44 39 41 39 41.4
Avg. 40.68
Quartz Glass - Paste + Sputter
8A 2.5 2.5 2.6 2.6 2.6 2.56
8B 3 3.4 3.1 3.2 3.2 3.18
8C 3.7 3.7 3.8 3.7 4.1 3.8
8D 4.9 5 5.1 5 5.3 5.06
8E 4.1 4.3 4.1 4 3.9 4.08
Avg. 3.736
Borosilicate Glass - Paste Only
9A 0.4 0.4 0.4 0.4 0.4 0.4
9B 0.4 0.4 0.4 0.4 0.4 0.4
9C 0.4 0.4 0.4 0.4 0.4 0.4
9D 0.4 0.4 0.4 0.4 0.4 0.4
9E 0.4 0.4 0.4 0.4 0.4 0.4
Avg. 0.4
Borosilicate Glass - Paste + Sputter
10A 0.4 0.4 0.4 0.4 0.4 0.4
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10B 0.4 0.4 0.4 0.4 0.4 0.4
10C 0.4 0.4 0.4 0.4 0.4 0.4
10D 0.4 0.4 0.4 0.4 0.4 0.4
10E 0.4 0.4 0.4 0.4 0.4 0.4
Avg. 0.4
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Table A-3. Post-adhesion resistance data.
Sample Test 1 Test 2 Test 3 Test 4 Test 5 Average
Borosilicate Glass - Sputter Coating w/ Copper
Tape as "Pads"
3D 30 29 31 29 30 29.8
3E 28 28 30 28 29 28.6
3F 28 26 27 33 29 28.6
3G 28 32 32 32 28 30.4
3H 29 27 31 30 28 29
Avg. 29.28
Quartz Glass - Paste Only
6A 0.4 0.4 0.4 0.4 0.4 0.4
6B 0.4 0.4 0.4 0.4 0.4 0.4
6C 0.4 0.4 0.4 0.4 0.4 0.4
6D 0.4 0.4 0.4 0.4 0.4 0.4
6E 0.4 0.4 0.4 0.4 0.4 0.4
Avg. 0.4
Quartz Glass - Sputter Only
7A 53 53 40 38 47 46.2
7B 39 43 39 43 42 41.2
7C 39 44 39 42 48 42.4
7D 42 36 36 38 34 37.2
7E 41 46 35 34 34 38
Avg. 41
Quartz Glass - Paste + Sputter
8A 0.4 0.4 0.4 0.4 0.4 0.4
8B 0.4 0.4 0.4 0.4 0.4 0.4
8C 0.4 0.4 0.4 0.4 0.4 0.4
8D 0.4 0.4 0.4 0.4 0.4 0.4
8E 0.4 0.4 0.4 0.4 0.4 0.4
Avg. 0.4
Borosilicate Glass - Paste Only
9A 0.4 0.4 0.4 0.4 0.4 0.4
9B 0.4 0.4 0.4 0.4 0.4 0.4
9C 0.4 0.4 0.4 0.4 0.4 0.4
9D 0.4 0.4 0.4 0.4 0.4 0.4
9E 0.4 0.4 0.4 0.4 0.4 0.4
Avg. 0.4
Borosilicate Glass - Paste + Sputter
10A 0.4 0.4 0.4 0.4 0.4 0.4
27
10B 0.4 0.4 0.4 0.4 0.4 0.4
10C 0.4 0.4 0.4 0.4 0.4 0.4
10D 0.4 0.4 0.4 0.4 0.4 0.4
10E 0.4 0.4 0.4 0.4 0.4 0.4
Avg. 0.4
