Sign up for our newsletter!

Subscribe form (en)

No spam. Simply good reading. Get your free subscription to Smoltek Newsletter infrequently delivered straight to your inbox.

Your data will be handled in compliance with our privacy policy.

Land side capacitors

Why capacitors?

Smoltek’s business division for the semiconductor industry, Smoltek Semi, focuses one hundred percent on capacitors. Why? After all, a capacitor is not a semiconductor. And what is the endgame for this venture? These are questions we address in this blog post.

A few weeks ago, we proudly announced that we had star­ted pro­duc­tion of capa­cit­ors in high-volume. But why the fuss about capa­cit­ors? After all, it is a severely price-pres­sured and already cheap com­mod­ity. And why is Smol­tek’s divi­sion for the semi­con­duct­or industry, Smol­tek Semi, doing this? A capa­cit­or is not a semi­con­duct­or! And what’s the plan for the future? All this is the sub­ject of this week’s blog post.

One of the toughest markets in the world

Yes, capa­cit­ors are a com­mod­ity. Yes, capa­cit­ors are cheap (they cost apiece just a frac­tion of a dol­lar). And yes, capa­cit­ors are under severe price pres­sure from the big boys.

So what on earth makes a small com­pany up in the north, not yet prof­it­able, bet on what must be one of the toughest mar­kets in the world?

The answer is two-fol­ded: The know-how to solve one of the elec­tron­ic industry’s biggest prob­lems in the con­tin­ued devel­op­ment of increas­ingly power­ful small devices. And the busi­ness oppor­tun­ity that comes with that know-how.

Let’s unpack what this means, start­ing with the busi­ness opportunity.

Why all the fuss about capacitors?

Every device that con­tains chips also con­tains capa­cit­ors. Your smart­watch, smart­phone, smart speak­er; your tab­let, laptop, and desktop com­puters; your tv, ste­reo sys­tem, and robot vacu­um clean­er. Every elec­tron­ic gad­get you own. The same applies to lar­ger sys­tems like cars, med­ic­al devices, and indus­tri­al-pro­cess controllers.

In short, capa­cit­ors can be found every­where. They are omni­present. And there is a colossal demand for them. Every year, more than a whop­ping one tril­lion capa­cit­ors are pro­duced worldwide.

Smol­tek aims to grab a slice of that pie.

So many capa­cit­ors are pro­duced – every year.

Huge market

It sounds like the hubris of a star­tup when Smol­tek claims to be able to cut even a slice of the pie. But it’s any­thing but hubris.

As you know, we have partnered with YAGEO, the world’s third-largest man­u­fac­turer of pass­ive com­pon­ents like capa­cit­ors. With our know-how and YAGEO’s sales and dis­tri­bu­tion chan­nels, we aim to jointly cap­ture one-third of the capa­cit­or mar­ket for the premi­um seg­ment of mobile phones except iPhones.

Of course, Apple knows what we have to offer, but we don’t pur­sue them for now. They are work­ing closely with a com­pet­it­or, and we believe they will not jump ship any time soon. 

We estim­ate that our address­able mar­ket buys between 3.5 and 4.5 bil­lion capa­cit­ors each year. So even if the price apiece is only a frac­tion of a dol­lar, the over­all sales impact is impressive.

Not a semiconductor

It may seem strange that Smol­tek focuses on an elec­tron­ic com­pon­ent that is not a semi­con­duct­or. But there is a per­fect reas­on for that. I have already hin­ted at what it is:

Capa­cit­ors are an abso­lute neces­sity for digit­al integ­rated cir­cuits of semi­con­duct­ors to work.To explain why, we need to go down the rab­bit hole of the inner work­ings of integ­rated cir­cuits and capa­cit­ors. If you don’t like the won­der­land of elec­tron­ics, skip this part and go straight to the last ques­tion: What’s the endgame?

Still here?

Good! Let’s fol­low the White Rabbit.

Book illustration showing the White Rabbit looking at his pocket watch.
In Lewis Carroll’s book The Nurs­ery Alice, Alice chases the White Rab­bit and unex­pec­tedly falls down a rab­bit hole, lead­ing her to Wonderland.


Although semi­con­duct­ors can be used for more than just digit­al integ­rated cir­cuits, digit­al integ­rated cir­cuits, or chips for short, are what we’re talk­ing about here. A chip con­sists of tran­sist­ors that act as elec­tric­al switches. Each tran­sist­or rep­res­ents a bit – a num­ber that can be one or zero. A tran­sist­or turns on power to rep­res­ent the value one and turns off power to rep­res­ent the value zero.

Turn­ing the power on and off can affect nearby devices. You may have exper­i­enced that the lights in your home blink when you turn on or off a kettle or oth­er elec­tric­al appli­ance that draws a lot of power. This is because the rap­id change in power demand cre­ates a short-lived pulse, called a tran­si­ent, which propag­ates from the appli­ance, through the wir­ing, to the lights. The same hap­pens when tran­sist­ors in a chip turn power on and off.

Troublesome transients

To make mat­ters worse, tran­sist­ors on a chip turn on or off sim­ul­tan­eously. They do so at the beat of a clock that ticks bil­lions of times every second. Each tran­sist­or con­trib­utes a little to what adds up to a sig­ni­fic­ant tran­si­ent. This tran­si­ent will propag­ate from the chip to oth­er chips and com­pon­ents if not addressed. That can dis­rupt (and even des­troy) the elec­tron­ics, with dev­ast­at­ing consequences.

Not only that. Tran­si­ents rush­ing through the power-feed­ing tracks make them act as trans­mit­ting anten­nas that send out radio waves. Oth­er tracks act as receiv­er anten­nas that pick up the radio waves and con­vert them into elec­tri­city. This way, the pulse is trans­mit­ted wire­lessly from the sup­ply tracks to oth­er tracks. Tracks that may trans­mit ones and zer­os that are at risk of flip­ping. Again, the con­sequences can be devastating.

Burning Microchip

Why capacitors are a necessity for semiconductors

To pre­vent these dev­ast­at­ing con­sequences, mit­ig­at­ing out­go­ing and incom­ing tran­si­ents is neces­sary. This is where capa­cit­ors come into play. When a capa­cit­or is used for this pur­pose, it’s called a decoup­ling capa­cit­or.

You can think of a decoup­ling capa­cit­or as a shock absorber for the voltage sup­ply to the chip. Quick voltage changes, both upward and down­ward, are smoothed out and become much smal­ler. They do this by absorb­ing and releas­ing energy as the sup­ply voltage fluctuates.

Some capa­cit­ors are light­ning-fast at absorb­ing the energy but can­not absorb much. Oth­ers are slower but can absorb more. There­fore, sev­er­al capa­cit­ors are often needed to pro­tect a chip. A single smart­phone pro­cessor today typ­ic­ally has eight decoup­ling capacitors.

That’s why capa­cit­ors are neces­sary for semi­con­duct­ors and the semi­con­duct­or industry. How­ever, the decoup­ling capa­cit­ors must be as close to the chip as pos­sible for it to work.

Why capacitors need to be close to the chip

In an ideal world, capa­cit­ors respond light­ning-fast to power surges, but in real­ity, they don’t. The reas­on is spelled para­sit­ic induct­ance.

Induct­ance refers to the prop­erty of an elec­tric­al con­duct­or by which a quick change in cur­rent flow­ing through it induces (hence the name) a voltage that opposes this change, effect­ively slow­ing the rate at which cur­rent can change.

Unin­ten­tion­al and unwanted induct­ance is said to be para­sit­ic. Para­sit­ic induct­ance is every­where, even in the wires between the capa­cit­or and the chip. The longer the wires, the more induct­ance and the great­er the res­ist­ance to sud­den changes. That is the oppos­ite of what we want to achieve.Thus, keep­ing the wires between a decoup­ling capa­cit­or and its chip as short as pos­sible is essen­tial. Ideally, the capa­cit­or should be inside the chip. But the next best thing for decoup­ling capa­cit­ors is to sit between solder balls under the chip. Such a capa­cit­or is called a land-side capa­cit­or (LSC).

Land Side Capacitors 2

Why capacitors need to be thin

It should be pretty obvi­ous why land­side capa­cit­ors must be small. They com­pete with the solder balls for space on the under­side of the chip. The typ­ic­al length and width of a capa­cit­or vary between half and a few millimeters.

They must also be thin because the dis­tance between the chip and the cir­cuit board is smal­ler than the dia­met­er of the solder balls. Com­monly, for com­puter chips, the solder balls are only 0.5 or 0.4 mil­li­meters in diameter.

In premi­um smart­phones, the require­ments are much tough­er than that. They require ultra-thin capa­cit­ors. We are talk­ing about tens of micro­met­ers instead of millimeters.

Challenges with ultra-thin capacitors

When the thick­ness of a land-side capa­cit­or gets down to 80 micro­met­ers, 60 micro­met­ers, or even 40 micro­met­ers, many prob­lems start to creep up.

The first chal­lenge that man­u­fac­tur­ers face is capa­cit­ance. This is the abil­ity to save energy. It is neces­sary to cre­ate suf­fi­cient capa­cit­ance in the small area avail­able without mak­ing the capa­cit­or too high.

Anoth­er chal­lenge for man­u­fac­tur­ers is to cre­ate ultra-thin capa­cit­ors that are not so brittle that they can­not be handled indus­tri­ally without breaking.

A third chal­lenge is the strength of mater­i­als. One tech­nique used today is to fill etched trenches in sil­ic­on sub­strates with an insu­lat­ing mater­i­al. How­ever, there are lim­it­a­tions in how deep these trenches can be and how tightly they can be placed.

Fourth, last but not least, these chal­lenges make the research and devel­op­ment of ever-thin­ner capa­cit­ors more com­plex and their pro­duc­tion more expensive.

This is where Smoltek’s CNF-MIM capa­cit­ors enter the stage.

What makes CNF-MIM capacitors unique

We expect CNF-MIM capa­cit­ors to have high­er capa­cit­ance than a deep trench sil­ic­on capa­cit­or (the closest com­pet­it­or) of the same length, width, and height.

In addi­tion, the CNF-MIM capa­cit­or is expec­ted to meet real-world require­ments with fly­ing col­ors: excel­lent capa­cit­ance sta­bil­ity, high break­down voltage, low leak­age cur­rent, and low series res­ist­ance and inductance.

To top it off, CNF-MIM capa­cit­ors aimed at high-end device seg­ments are expec­ted to be cheap­er to pro­duce, so we can com­pete on price and still have a good mar­gin for capacitors.

Smoltek R&D-team at MC2 nanotech lab

The endgame

Is the com­mer­cial­iz­a­tion and mass pro­duc­tion of CNF-MIM capa­cit­ors the endgame of Smoltek’s explor­a­tion in the semi­con­duct­or territory?


CNF-MIM capa­cit­ors are just one of many applic­a­tions in the semi­con­duct­or field for which car­bon nan­ofibers can be used. If you’ve been around for a while, you might remem­ber Smol­TIM, SmolINCO, and SmolINPO. Our pat­ent-pro­tec­ted solu­tions for heat dis­sip­a­tion inside chips, inter­posers with built-in decoup­ling capa­cit­ors and rein­forced con­nec­tion points for mul­tiple dies, and solder balls with ultra-fine pitch (down to 5 micrometers).

How­ever, we chose CNF-MIM capa­cit­ors because it was pretty obvi­ous busi­ness-wise. There is an immin­ent need for ultra-thin capa­cit­ors, and the mar­ket is vast.

Our pat­ents pro­tect the oth­er tech­no­lo­gies, so we can safely focus on launch­ing sales and rolling out mass pro­duc­tion of CNF-MIM capa­cit­ors. Once it is up and run­ning, we can return to the oth­er tech­no­lo­gies and con­sider which one to bring to the mar­ket next.

Unequivocal proof of concept

Anoth­er bene­fit of start­ing with pro­du­cing CNF-MIM capa­cit­ors is that it offers unequi­voc­al proof for foundries that our tech­no­logy works in their environments.

Foundries are the factor­ies that make the semi­con­duct­or itself. They are argu­ably the most expens­ive factor­ies humans have ever built. Each costs sev­er­al bil­lion US dol­lars. Thus, their own­ers and investors don’t take any risks. They can’t afford it.

It is too risky for them to insert Smol­tek’s car­bon nan­ofiber grow­ing tech­no­logy into their CMOS chip man­u­fac­tur­ing pro­cess without proof that it works.

Now they get that proof.

The same tech­no­logy used by foundries makes the CNF-MIM capa­cit­ors. Of course, with the addi­tion of our car­bon nan­ofiber growth tech­no­logy. And that’s the point. Our tech­no­logy works with theirs without caus­ing any problems.

Over to you

Well, that’s pretty much all there is to know about why we chose capa­cit­ors as the first com­mer­cial­ized applic­a­tion of car­bon nanofibers.

What do you think of the blog post? Was it too long? Too tech­nic­al? Or maybe just right? Some­thing you have missed? Head over to Linked­In and leave a comment.

Sign up for our newsletter!

Subscribe form (en)

No spam. Simply good reading. Get your free subscription to Smoltek Newsletter infrequently delivered straight to your inbox.

Your data will be handled in compliance with our privacy policy.

Latest posts