Is it just me? Or has anyone else noticed the high incidence of cracked screens on iPhones? (Sarcasm intended.) I 'm not sure, but I don't recall having seen one more than six months or so old that did not have a crack. I even seem to remember seeing something about Apple planning to offer repair kits as standard add-ins to their newest model, so the user would be able to replace both the screen and the Lightning connection (another weak point in their products).
Recently, after my son Doug gave my wife Nancy his old Kirkland (made by Rexton) hearing aids, she had to give up her trusty Android phone and get an iPhone, in order to use a proprietary Bluetooth streaming transmitter that Apple had developed in cooperation with a limited number of hearing aid manufacturers. To give the Devil his due, this is a marvelous innovation! There is so little lag time, it is essentially like having wired headphones on. It is a little annoying that they have chosen to go the proprietary route with this innovation, like with all of their best stuff. But that's a minor quibble - not everyone is like Benjamin Franklin with the lightning rod. And certainly, Franklin made a lot of money with other products. But I digress. Sure enough, it wasn't long before she had a cracked screen in two places. So, I've been thinking, why doesn't Apple just license the glass formulation that all the other manufacturers use and be done with this problem?
A couple of days ago, I was reminiscing (AKA bragging to Nancy) about some of my more astute simple fixes to different semiconductor industry manufacturing processing problems I encountered in my career, when I sat bolt upright and practically screamed, "NO WAY!" I grabbed my wife's iPhone! "WAY!", as I looked, as best I could, at the edges of the screen!
The particular fix I had been telling Nancy about occurred, as I recall, in 1984. At the time, I was Manager and Process Engineer for the Photomask Blanks shop of the Photomask Department at Texas Instruments in Dallas, TX. The semiconductor industry was closing in on megabit memory chips, and one of the enabling new developments was the introduction of quartz photomask blanks. Because of the magnitude-smaller coefficient of thermal expansion of quartz, quartz was replacing Hoya's LE-30, the dominant plate of the day, in photomasks for the highest density integrated circuits. LE-30 had supplanted soda-lime glass (both green and White Crown) a few years earlier when non-contact projection printing equipment had been introduced, in the 16-kilobit era, as it had a similar smaller coefficient of expansion advantage over soda-lime. The advantage was due to the need to allow a better overlay of stacked patterns on wafers, especially toward the edges of the wafer, when using equipment that causes the photomask to heat up as a batch of wafers is being patterned. At that time, 5" X 5" quartz plates were costing about $500 each.
The Japanese company TDK, well known for its recording tapes, but also a player in other ferromagnetic-related industries, came up with the idea of drawing a ribbon of molten quartz through a platinum die and then cutting the ribbon into squares, as the source for their entry into the quartz photomask blank market, anticipating a $100 price point. This was a huge innovation and a significant departure from the existing process of cooling off a boule of quartz and then sawing it up into slices, then squares, and then grinding and polishing them down to the final flat and polished thickness.
As we were evaluating the TDK plates, we experienced a problem with a high incidence of cracking in the corners of the plates in our ultrasonic cleaning baths. When they visited the next time, I pointed this out and told them, "Your plates have very sharp edges and corners, so a lot of stress resides in those edges and corners. You need to put a little radius (rounding) on all your edges and corners to relieve that stress." (This was not some ground-breaking insight on my part - it was standard practice by all other vendors.) Then I took them over to visit George (I can't remember his last name), the crusty old guy that made all of the quartzware for TI's Central Research Laboratory. I asked him to put one of their plates under a polariscope, and when he did, a veritable rainbow of colors emanated from each edge and, especially, each corner. He told them, "You need to put a little radius on all your edges and corners to relieve that stress."
About a month later, TDK came in for another visit and reported what they had done back in Japan: They had put together a 14-engineer task force and seriously attacked the problem with brute force, as is their wont. (Think Russian Army tactics.) They had conducted a series of ball drop tests from various heights and angles. They had done ultrasonic bath tests, etc., etc. etc. And they had come up with a definitive solution, "We need to put a little radius on all the edges and corners of our plates." Somehow, I managed to keep a straight face.
Not so, right now! I am howling! 😂 Really!
How has Apple, the repository of all that fantastic brainpower, not picked up on this almost trivially simple solution to their problem - 39 years after old George took one look at TDK's quartz photomask plates and confirmed what I had told them? Have all of Apple's competitors just been snickering up their sleeves all these years? I mean - I know there is a lot of hubris at Apple, but are they that elitist and insular? A big part of my career was sussing out the simple little low-tech details that the guys much, much smarter than me overlooked. Has no-one like me ever worked at Apple. Nah, probably not. JOATs need not apply, I suppose.
(Sadly, TDK's plates did not fare well in the market, due to inclusions near the ribbon-edge sides of the plates. In other words, they made the die too narrow, not leaving enough extra width to trim off the edge-effect scuzz. Another simple little detail was not accounted for by the brilliant guys,)
