In this post, pores from four different structures are compared. Those four different structures are nitride/silicon/nitride (NSN), nitride/silicon/oxide (NSO) , oxide/silicon/nitride (OSN) and oxide/silicon/oxide (OSO) . The thicknesses of nitride, oxide and silicon are 30nm, 30nm and 25nm, respectively. Wafers…

In my previous post of Morphology evolution in pnc-Si membrane (2), see https://trace-bmps.org/datablog/?p=14769&preview=true , I showed that membranes (30SiN-25Si-30SiN) annealed at 700C show us an intermediate morphology in the pnc-Si membrane. I did some further investigation in the past week…

In the last post, we have discussed the intermediate state of the membranes which shows the irregular shape pores and silicon nanocrystals after annealed at 700C. Last week I did a quick test on the same nitride membrane with a…

In this post, I would like to sum up all different annealing scenarios, which corresponding to different morphologies of the pnc-Si membrane so far we have observed. It should be very helpful to understand the evolution of the pore formation…

Now we already confirmed that pores are able to form in both oxide/silicon/oxide and nitride/silicon/nitride system. Here comes an interesting question- how about nitride/silicon/oxide and oxide/silicon/nitride system? In the past week, another two different stacks including SiN(30nm)/ a-Si(25nm)/SiO2(30nm) and SiO2(30nm)/a-Si(25nm)/SiN(30nm)…

Last week, I deposited silicon nitride/ amorphous silicon/ silicon nitride stack and then annealed the free standing stack after etching the substrate. The nitride film was deposited with 25W bias and the silicon film with 5W bias. The thickness for…

A few weeks ago, professor Mike Aziz in Harvard University helped to annealed two samples and in-situ imaged the early stage of pore formation using their Jeol2010-hot-stage-TEM. The oxide seemed intact during the process. The sample was unannealed 20(bottom)/15(a-si)/10(top) three…

The thickness of bottom oxide in the ‘sandwich structure’ is also a key factor to affect the pore morphology. In last few weeks I deposited five wafers with different bottom oxide thicknesses and they were 05/15/20, 10/15/20, 20/15/20, 40/15/20 and…

Last few weeks, I deposited a couples of wafers to test the effect of oxide thickness on pores. In addition to previous data, I deposited another two wafers, one with 1nm top oxide and the other with 100nm top oxide.…

Last week, I did another two wafers with different top oxide thicknesses to verify my hypothesis about the top oxide thickness effect on pores. The wafers were 20/15/03(bottom/middle/top) and 20/15/40. According to the hypothesis, the porosity of 20/15/03 would continue…