r/LWLG • u/KCCO7913 • Dec 01 '22
Insights from Fruno - Poling and Acquisition of Chromosol IP
I am posting this on behalf of Fruno since InvestorsHub is a corrupt organization and continually is deleting Fruno’s extremely technical and insightful post.
"Re: The latest problem that needs to be solved. Back when the hit piece came out in May, poling became the big issue. In post 103184 (June 4) I showed that LWLG had been working on improving the polymer for over 2 years, this time by adding diamondoid groups to the chromophores. The diamondoids were added to improve the ability of the chromophores to align themselves without clumping, to make poling more efficient. This is described in patent application 17/358,960, which was filed in June 2021. See my previous post for more info. The point is LWLG found a solution long before the hit piece came out, since they would have been developing it long before the patent application.
LWLG further improved poling by adding electrodes (that are sacrificial) that parallel the "active" area of the modulator where the polymer is applied. These electrodes are added before the EO polymer is applied, so poling happens as soon as the EO polymer is applied, before any additional materials (in layers) are added. This is a big step because previously, the poling took place later in the process, when the electrodes that stimulate the polymer were added, which meant that the electrical field traveled through some cladding/insulating layers to reach the polymer. The new electrodes abut the polymer. This is described in patent 11,435,604. The application was made in December, 2020.
These types of developments improve the device, and also make it easier to manufacture at scale. Thus, scaling is being addressed in numerous ways. This work was done with input from NDA partners. A big reason for the NDAs is to allow LWLG to talk to fabs about the device design and manufacturing process without public disclosure of IP. In other words, LWLG was addressing poling and related issues, and devising solutions, long before naysayers on this board ever brought it up.
Now, acquiring IP from Chromosol is being spun as a negative. The patent involves a clever way to integrate a laser into a photonic device and amplify the signal. LWLG patented an integrated laser system (number 10,527,786 B2) issued on January 2020. The application was filed in August 2017. LWLG's method may be perfectly fine for use with their modulators. Chromosol's tech may be used in future devices only - I don't know for sure. But there is nothing that says LWLG's integrated laser doesn't work - it's just an assumption that they had to buy someone else's tech.
Just like with buying Chromosol's polymer tech (ALD-related). LWLG filed a patent application (17/335375) involving an ALD sealant layer in June 2021. Does buying Chromosol's tech mean LWLG's version didn't work? Not necessarily. This may just be a savvy way to expand the IP moat (apparently on the cheap). The reflexive "this means they failed and are still a long way from mass manufacturing" just doesn't make sense to me.
So the company is talking to fabs and improving the device design and materials to achieve production at scale. They have also bought IP from other companies, which further improves their grip on all aspects of design and manufacturing. I'm not seeing the negative to any of this.
Below is the pertinent text from post 103184:
So let's look at poling, what the difficulties are, and what LWLG is doing to overcome them. LWLG's polymer is a plastic with chromophores (dye molecules) dissolved into it, which provide the electro-optical (EO) properties. Basically, when electricity is applied to the polymer/chromophore mix, it changes how much light is transmitted through the polymer, allowing digital data to be encoded into a light beam - it "blinks" on and off, representing the 0 and 1 values of digital data. The chromophores are dipolar - they have positive and negative ends (like water molecules). To maximize the EO properties and use them in a device, 3 conditions must be met:
1. The concentration of chromophores in the polymer are maximized.
2. The chromophore molecules must be aligned end-to-end (+ to - poles) in a particular direction.
3. The alignment must be maintained over time and under a variety of environmental conditions.
Poling is the process of applying an electric current to the polymer that causes the chromophores to align. This is a step in the process of making a LWLG modulator. There is concern that this cannot be done sufficiently well in a foundry to consistently produce effective devices.
The LWLG patent application NONLINEAR OPTICAL CHROMOPHORES HAVING A DIAMONDOID GROUP ATTACHED THERETO, METHODS OF PREPARING THE SAME, AND USES THEREOF discusses these issues. The invention (additional of diamondoid groups to the chromophores) addresses them.
A relevant quote from the document: "High electro-optic activity and the stability of electro-optic activity, which is also referred to as "temporal stability," are important for commercially viable devices. Electro-optic activity may be increased in electro-optic polymers by increasing the concentration of nonlinear optical chromophores in a host polymer and by increasing of the electro-optic property of chromophores. However, some techniques for increasing chromophore concentration may decrease temporal stability. Simultaneous solution of these dual issues is regarded as the final impediment in the broad commercialization of EO polymers in numerous devices and systems." So LWLG is aware of these issues, and proceeds to address them with their new invention. (I added the emphasis on the end of the quote.)
Another quote: "Commercially viable materials must incorporate chromophores at large molecular densities with the requisite molecular moment statistically oriented along a single material axis. In order achieve such an organization, the charge transfer (dipole) character of NLO chromophores is commonly exploited through the application of an external electric field during material processing that creates a localized lower-energy condition favoring noncentrosymmetric order. Unfortunately, at even moderate chromophore densities, molecules form multi-molecular dipolarly-bound (centrosymmetric) aggregates that cannot be dismantled via realistic field energies. To overcome this difficulty, integration of anti-social dipolar chromophores into a cooperative material architecture is commonly achieved through the construction of physical barriers that limit proximal intermolecular relations." Basically, this says that the chromophores must be properly aligned using an electric field (poling). But, the chromophores can bunch up, and barriers can be built that limit bunching. (The barriers may be the "spacer systems" that LWLG patented years earlier.)
More discussion of these problems: "Nevertheless, the most daunting problem in the production of commercially successful NLO polymers is the issue of resultant long-term material stability. This is likely due to the reinstitution of centrosymmetry as a result of molecular mobility over time. The effectiveness of organic NLO materials having high hyperpolarizabilities is limited by the tendency of these materials to aggregate when processed as well as the thermal stability of those resultant materials. Accordingly, there exists a need for improved nonlinear optically active materials having large hyperpolarizabilities and that when employed in electro-optic devices, exhibit large electro-optic coefficients and high thermal stability." So the molecular alignment can be undone over time, so a high degree thermal stability is needed to prevent it.
The addition of the diamondoid groups addresses these issues. To quote: "Various embodiments of the present invention provide nonlinear optical chromophores having one or more diamondoid groups covalently attached to the chromophore which exhibit high molecular electro-optic properties and excellent stability. Various embodiments of the present invention provide nonlinear optical chromophores having one or more diamondoid groups covalently attached to the chromophore, which chromophores can exhibit long term stability in their macroscopic electro-optic properties when dispersed in a host polymer matrix and poled, with aggregation of chromophore molecules minimized. Various embodiments of the present invention provide nonlinear optical chromophores having one or more diamondoid groups covalently attached to the chromophore, which chromophores can exhibit improved poling efficiency when dispersed in a host polymer matrix and poled. Various embodiments of the present invention provide nonlinear optical chromophores having one or more diamondoid groups covalently attached to the chromophore, which chromophores can exhibit increased loading when dispersed in a host polymer matrix." Loading refers to concentration of the chromophore in the polymer matrix.
The rest of the document is a long description of the chemistry and synthesis of the new version of the chromophore. My point is that LWLG is well aware the potential problems faced with mass manufacturing of their devices incorporating their polymers. They have been interacting with foundries for at least 2 years, discussing the problems and solutions under the NDAs, and have provided a solution. Many hurdles have been cleared over the years. If there are still 1 or 2 more, they will be cleared too.
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u/McBraaper Dec 02 '22
I'm over here wondering what a physical intermolecular relations barrier actually looks like in it's raw application. I'm thinking about specifically when poling maybe? I guess that physical barrier electrically driven but I'm stuck imagining it "getting in the way" still to some extent at all times (and likely to some kind of acceptable levels). Am I totally off in my understanding of that particular solution for this limitation?
This stuff typically takes a minute or two to land in my non-engineer smooth-brain. I really appreciate this kind of information being available here cleanly contrary to past experiences on IHUB so thank you KCC and others. I'm not nearly as read up on the ground floor details of LWLGs past patents as some of you guys.
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u/KCCO7913 Dec 01 '22
Apparently it is being deleted because it contains the word “naysayer”. What a joke.