Building transistors today is done with lithography, which is a “top-d

Question

Building transistors today is done with lithography, which is a “top-down” process that uses patterning to create the complex layers that make up the transistor structure. It’s a bit like exposing a negative on photographic paper to get the pattern you want and then using this pattern as a template to place each material – metal, insulator or semiconductor – in exactly the right location. This process has worked successfully since the 1950s. But as we get to ever-smaller dimensions, new approaches to building nano-scale devices will be required. At IBM’s T.J. Watson Research Center, we use a technique called  self-assembly  to grow and directly control nanostructures that could one-day form parts of integrated circuits. Self-assembly looks at a “bottom-up” approach that builds nanostructures in a way that is dictated by physics rather than by an imposed pattern. In some ways it’s like farming, in that you plant seeds to grow a crop, and then support the growth with the right conditions to get the result you want.

Exploring self-assembly doesn’t mean we are ready to throw away today’s approach; instead, we want to use top-down strategies that we have already learned over many years, and combine them with new tricks that use self-assembly. Think of it as water splashing onto a pane of glass. It spontaneously forms little hemispheres because of surface tension. But the positions and sizes of the droplets are random. Now imagine there is a scratch on the glass. Water droplets form on the scratch, because it is a good, low-energy place for the water molecules to stick. We have now combined self-assembly (make a hemispherical droplet on this surface) with an imposed pattern (make a droplet on this part of the surface by using carefully placed scratches.) The result is that we can build more complicated patterns. Flexible, customized patterns—like this water example, but on the nano-scale —help us build integrated circuits. The more precisely we can direct this self-assembly, the more versatility we can achieve.    1 
What does the passage do as a whole

A. Explains why self-assembly is the best approach to make integrated circuits 
B. Explains how the “top-bottom” approach is better than the “bottom-up approach”
C. Shows how the “bottom-up” and the “top-bottom approach” can both complement and hinder development of nano- scaling techniques
D. discusses how “top-bottom approach” has been discarded because of the new approach
E. Reasons that future necessitates an innovative approach

2

According to the author the primary difficulty in using top- bottom approach is that

A. The new approach is easier to work with
B. The task of working on ever-smaller dimensions is way too complicated for the approach
C. This process has worked since 1950s till now only
D. It is not future ready
E. It is as tedious a task as exposing a negative on photographic paper

3

Why does the author use the example of water splashing on a pane of glass

A. Explain how integrated circuits can be made only by self-assembly
B. To provide an analogy for the combined method
C. To illustrate bottom- up approach
D. To raise questions about bottom-up approach
E. To evaluate the combined method

4

Which of the following best expresses the function of the first paragraph in relation to the passage as a whole

A. To establish the parameters of an ensuing debate
B. To identify problems in one of the processes, which are then explored in greater details
C. To provide a backdrop for a discussion of a modern day approach
D. To discuss an existing prototype that the author admires
E. To introduce opposing viewpoints, which are then evaluated

5

Which of the following titles best summarizes the passage as a whole

A. A look at the history of nanostructures
B. Pointing out limited usefulness of the “top-down” process
C. Detailed study of transistors
D. At the threshold of new approach 
E. How top-bottom approach works

GMAT VERBAL Daily Challenge RC/CR/SC (2022) Project

ElninoEffect · Accepted Answer

Question 1: What does the passage do as a whole

A. Explains why self-assembly is the best approach to make integrated circuits
No, there is a comparison between the two approaches so we can say it's better than the other approach but saying it's the best approach is farfetched.
B. Explains how the “top-bottom” approach is better than the “bottom-up approach”
Partially correct as it is explained in the first paragraph but not as a whole.
C. Shows how the “bottom-up” and the “top-bottom approach” can both complement and hinder development of nano- scaling techniques
Its all jumbled. Top down approach is a hindrance for nano scaling not bottom-up.
D. discusses how “top-bottom approach” has been discarded because of the new approach
No such thing has been said.
E. Reasons that future necessitates an innovative approach
Yes, due to nano scaling there is demand for a new approach.

Question 2: According to the author the primary difficulty in using top- bottom approach is that

A. The new approach is easier to work with
That's not the reason.
B. The task of working on ever-smaller dimensions is way too complicated for the approach
Exactly why there is a need for the change.
C. This process has worked since 1950s till now only
Although its been working since 1950s it is still perfectly fine for the transistors it's the nano scaling where the technology is hampered.
D. It is not future ready
Its too generic we are looking for a specific reason.
E. It is as tedious a task as exposing a negative on photographic paper
That's not the reason.

Question3: Why does the author use the example of water splashing on a pane of glass

A. Explain how integrated circuits can be made only by self-assembly
The term water splashing is used in second paragraph and second paragraph is all about how to combine two technologies.
B. To provide an analogy for the combined method
Yes, that's what it is actually doing basically summing up the second paragraph.(describing combined method)
C. To illustrate bottom- up approach
No. as discussed in A and B
D. To raise questions about bottom-up approach
See A and B
E. To evaluate the combined method
We are not discussing pros and cons we are drawing an analogy.

Question 4: Which of the following best expresses the function of the first paragraph in relation to the passage as a whole

A. To establish the parameters of an ensuing debate
We are not debating anything here we are discussing the two technologies.
B. To identify problems in one of the processes, which are then explored in greater details
Only one problem has been mentioned not sure about what other problems are.? And no such exploitation on the problem has been done.
C. To provide a backdrop for a discussion of a modern day approach
Yes by introducing a modern day approach in the last part of the first paragraph it is setting the platform for modern day approach to be discussed further.
D. To discuss an existing prototype that the author admires
Author is not taking any sides here.
E. To introduce opposing viewpoints, which are then evaluated
No viewpoints have been presented just the facts.

Question 5: Which of the following titles best summarizes the passage as a whole

A. A look at the history of nanostructures
The word history bugged me off, as bottom up approach is future technology.
B. Pointing out limited usefulness of the “top-down” process
Its only partially correct many other things have been discussed.
C. Detailed study of transistors
We are not confined to only transistors we are discussing about IC's too.
D. At the threshold of new approach
This sounds good, as the older technology will become redundant if no steps are taken.
E. How top-bottom approach works
Only partially correct.

P.S- If I have screwed this up carcass please allow me delete this post.

carcass · Answer

I do not think during the GMAT is allowed to you to see immediately your answers if right or wrong

ElninoEffect · Answer

I was asking when the answers are revealed. I have the opportunity to cancel the score know.

carcass · Answer

Question #1: The OA will be automatically revealed on Monday 10th of January 2022 04:13:50 AM Pacific Time Zone

Thank you Sir to support this community

mridultulsyan · Answer

Could someone pls explain why in Q2 option B is incorrect and D is the right option. B seems more apt.

kntombat · Answer

mridultulsyan , 
I would like to offer my take on your question.
In my opinion, Option B in question 2 is wrong because it is too strong an option.
If you look at the 1st paragraph it clearly says the following  "But as we get to ever-smaller dimensions, new approaches to building Nano-scale devices will be required." 
from this sentence we can say that lithography could also work to build Nano-scale devices but new approaches are preferred to do the same.

That's why option D is right in my opinion.

Building transistors today is done with lithography, which is a “top-d

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GMAT Reading Comprehension (RC) Questions

Building transistors today is done with lithography, which is a “top-d

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