📚 AI back-end series Previous: Substrates are a “volume beta,” test sockets are a “consumables beta” — same AI tailwind, completely different structures

Yesterday’s post compared substrates and test sockets structurally. Today we go one step further and compare them numerically. Eleven AI back-end names lined up on the same yardstick — 2026 YTD return, operating-profit growth, 2026E and 2027E PER, 2026E operating margin. Even within “AI winners,” how much each has already moved and how much room is left differ wildly. One table tells you most of the story.

Key takeaways

• On pure “cheapness”: SK hynix (2027E PER 5.2x), Samsung Electronics (5.6x), Haesung DS (15.4x). But the memory megas are dominated by “cycle-peak” risk.
• On “growth-adjusted multiple”: Daeduck Electronics (2027E PER 27.1x vs OP +34%) and Simmtech (20.0x vs OP +59%) are the sharpest setups.
• “Already done the work”: Samsung Electro-Mechanics (2026 YTD +296%, 2026E PER 61.9x), Isu Petasys (+346% in 2025 but only +7% YTD 2026), Simmtech (+352% in 2025).
• “Quality, but the multiple is rich”: LEENO Industrial (OPM 48.6%, 2026E PER 41.2x), ISC (2026E PER 58.5x).
• “Growth at a fair price”: TSE (2026E OP +82%, PER 29.4x).
• Bottom line: within AI back-end, attractiveness ranks substrates > test sockets > memory megas. Within substrates, Daeduck and Simmtech are the cleanest.

1. How the comparison is built

1.1 The data set

Reference date: May 15, 2026 close.

1.2 Why 2027E PER matters more than 2026E PER

2026E PER:
→ Multiple on this year's expected earnings
→ Already absorbing 1Q26 reality
→ Affected by short-term quarterly noise

2027E PER:
→ Multiple on next year's expected earnings
→ Reflects "will the cycle persist?"
→ Where the market's true view shows up

Examples:
Company A: 2026E PER 30x, 2027E PER 28x
→ Market expects earnings roughly flat
→ "Stable growth" archetype

Company B: 2026E PER 30x, 2027E PER 15x
→ Market expects earnings to nearly double
→ Or the market hasn't bought in yet → undervalued setup

Company C: 2026E PER 7x, 2027E PER 5x
→ Market doubts earnings durability
→ "Cycle-peak fear" — typical of memory megas.

1.3 Why OP growth has to be read with PER

PER alone is misleading.

Same PER 30x:
A: OP YoY +20% → 30 / 20 = 1.5
B: OP YoY +60% → 30 / 60 = 0.5
B is far more attractive.

This is the PEG ratio (PER / OP growth).
≤1.0 attractive, 1.0–2.0 fair, >2.0 expensive.

This post visualizes a simplified version —
a 2027E PER × 2027E OP YoY matrix.

2. Eleven stocks, one table

2.1 The basic comparison

2.2 How to read it

Down the columns:
- High 2025 return = already run a lot
- High 2026 YTD = still strong this year
- High 2026E OP YoY = earnings explosion expected
- Low 2027E PER = market doubts earnings persistence

Across the rows:
- Was the name strong last year too (+200%+)?
- Still strong this year (+100%+)?
- Yet not punitive on the multiple (2027E PER ≤ 30)?
- Decent operating margin (2026E OPM ≥ 20%)?

Names that hit all four = most attractive.

3. Reading each bucket

3.1 Memory megas — “cheap, but cycle-peak fight”

The numbers look stunning:
SK hynix: 2027E PER 5.2x, OPM 75.9%
Samsung Electronics: 2027E PER 5.6x, OPM 51.1%
→ In normal industries, PER 5x screams "bankruptcy risk"
→ Memory is different. When the cycle turns, earnings fall by half+.

Why the market still applies 5x:
"We'll grant you 2026 earnings.
 We are not convinced 2027–28 earnings will stay here."

This is the heart of memory investing:
- The stock looks cheapest right before the cycle peaks
- The moment the cycle turns, PER spikes (because EPS collapses)
- Buying "trough PER" can mean selling at the actual top.

Read:
SK hynix     — best case if HBM supercycle runs into 2027.
               Large drawdown if the cycle turns.
Samsung      — strike risk + HBM share doubts = discount vs. SK hynix.
Jeju Semi    — no consensus available; excluded from direct compare.

3.2 Test sockets — “quality intact, multiple full”

LEENO Industrial:
- OPM 48.6% (top tier of Korean manufacturing)
- 2027E OP YoY +24.1% (steady growth)
- 2027E PER 33.4x
→ Read: highest quality, but multiple is full.

ISC:
- OPM 31.8% (very good)
- 2027E OP YoY +41.4% (strong growth)
- 2027E PER 43.2x
→ Read: cleanest AI data-center beta, but tightest multiple.

TSE:
- OPM 17.0% (lowest among the three)
- 2027E OP YoY +21.5% (decent)
- 2027E PER 24.7x (cheapest in test sockets)
- 2026 YTD +215% (already running hard)
→ Read: best price-for-growth balance, but chase risk after the YTD move.

Read:
Don't treat LEENO and ISC as the same "test-socket stock."
- LEENO = quality compounder (hold-and-own)
- ISC   = direct AI data-center beta (momentum)
- TSE   = the balanced "value-for-growth" option.

If you must pick one new entry:
- 1-year hold:        LEENO (stability)
- 6-month momentum:   TSE (value-for-growth)
- Direct AI exposure: ISC (speed).

3.3 Substrates — the most interesting bucket

Samsung Electro-Mechanics:
- 2026 YTD +296% (among the top movers)
- 2026E PER 61.9x → 2027E PER 41.9x
- OPM 11.8% (blended across MLCC + FC-BGA)
→ Great company, but chasing is inefficient.

Daeduck Electronics:
- 2025 +206%, 2026 YTD +188% (persistent strength)
- 2026E PER 36.1x → 2027E PER 27.1x
- OPM 15.5% (top of substrate group)
- 2026E OP YoY +375%, 2027E +34%
→ The numbers justify the leadership premium.

Simmtech:
- 2025 +352% (biggest mover)
- 2026 YTD +103% (still strong)
- 2026E PER 31.0x → 2027E PER 20.0x (lowest)
- 2026E OP YoY +1,234% (loss → profit)
- 2027E OP YoY +58.7%
- OPM 8.6% (margin needs to expand further)
→ Turnaround + multiple appeal — but margin durability needs proof.

Haesung DS:
- 2026 YTD +57% (lagger of the group)
- 2026E PER 20.3x → 2027E PER 15.4x (cheapest of the group)
- 2026E OP YoY +99.6% (very strong)
- OPM 11.4%
→ The cheapest candidate. Weaker leadership profile,
  but the price-for-growth is good.

Isu Petasys:
- 2025 +346% (a parabolic year)
- 2026 YTD +7% (resting this year)
- 2026E PER 35.6x → 2027E PER 26.7x
- OPM 21.1% (highest in substrates)
→ All the move came pre-emptively last year; resting.
  Wait for relative-strength recovery.

4. The growth-vs-multiple matrix — the most intuitive view

4.1 2027E PER × 2027E OP YoY

X-axis: 2027E operating-profit growth
Y-axis: 2027E PER

low ← PER → high
+5x  --10x---20x---30x---40x---50x  PER

+60% │              Simmtech
     │
+50% │                          Samsung Electro-Mechanics
     │
+40% │                              ISC
     │
+35% │       SK hynix
     │
+34% │                    Daeduck Electronics
     │
+36% │       Haesung DS
     │
+33% │                   Isu Petasys
     │
+27% │       Samsung Electronics
     │
+24% │                              LEENO Industrial
     │
+22% │                   TSE
     │
     └──────────────────────────────

How to read:
- Upper right (high PER + low growth): expensive
- Lower left (low PER + high growth):  best value
- Upper left (low PER + low growth):   trap
- Lower right (high PER + high growth): momentum

Most attractive zone:
Left (low PER) + top (high growth) = Simmtech, Daeduck

Most punitive zone:
Right (high PER) + mid growth = LEENO

Special zone:
Far left (very low PER) = SK hynix, Samsung Electronics
→ Looks cheap, but cycle-peak risk lives here.

4.2 Reading “real value” from the matrix

Simplified PEG (PER / growth):

Simmtech:        20.0 / 58.7 = 0.34  ★★★★★
SK hynix:         5.2 / 36.0 = 0.14  (memory exception)
Samsung Elec:     5.6 / 26.7 = 0.21  (memory exception)
Haesung DS:      15.4 / 36.6 = 0.42  ★★★★
Daeduck:         27.1 / 34.4 = 0.79  ★★★★
Isu Petasys:     26.7 / 33.0 = 0.81  ★★★
Samsung E-M:     41.9 / 50.0 = 0.84  ★★★
TSE:             24.7 / 21.5 = 1.15  ★★★
ISC:             43.2 / 41.4 = 1.04  ★★★
LEENO:           33.4 / 24.1 = 1.39  ★★

Bucketing:
- ≤ 0.5: very attractive
- 0.5–1.0: attractive
- 1.0–1.5: fair
- ≥ 1.5: expensive

Memory megas are a special class — cycle peak.
On normal terms, Simmtech > Haesung DS > Daeduck.

LEENO looks the worst on PEG, but its
earnings stability and predictability are unmatched.
It deserves a "premium multiple" — PEG alone underrates it.

5. Cross-bucket — “where should fresh capital go?”

5.1 Substrates vs test sockets vs memory

Scenario 1: "AI back-end shortage cycle continues"
→ Substrates most attractive
  shortage → ASP hike → margin expansion
  Daeduck Electronics, Simmtech are top picks

Scenario 2: "AI chip diversification has further to run"
→ Test sockets most attractive
  new chip = new socket
  LEENO Industrial, ISC are top picks

Scenario 3: "HBM supercycle extends into 2028"
→ Memory megas most attractive
  SK hynix is top (OPM 75.9%)
  But you have to accept cycle-peak risk

Safest framing:
Diversify across the three buckets — 4:3:3 or 5:3:2.

5.2 Illustrative allocation across the 11

Just an example. Not real money advice.

Aggressive (short-term momentum tilt):
Daeduck 25% / Simmtech 20% / Samsung E-M 15%
ISC 15% / TSE 10% / SK hynix 15%

Balanced (growth + stability):
Daeduck 20% / LEENO 20% / SK hynix 15%
Samsung E-M 15% / Haesung DS 10% / Simmtech 10%
TSE 10%

Defensive (quality tilt):
LEENO 30% / Samsung E-M 20% / SK hynix 20%
Daeduck 15% / Haesung DS 15%

Allocation rules:
1. Higher OPM = larger weight
2. Heavier multiple burden = smaller weight
3. Don't concentrate in a single bucket
4. Cap cycle-risk names.

6. One-line read by name

6.1 Author’s attractiveness ranking

6.2 Pre-entry checklist

Before buying any of these:

1. Macro gate (see the prior post)
   - US 10-year below 4.45%
   - Brent below 105 USD
   - USD/KRW below 1,480
   - VIX below 18
   → 2–3 of 4 stable before new buying.

2. Stock-level catalysts
   - Quarterly print dates
   - New customer LTA announcements
   - New-fab ramp schedule (LEENO)
   - 2Q guidance

3. Scaling rules
   - No one-shot buys
   - Adjust size as macro gates flip
   - Prefer pullback entries over chasing.

4. Bucket diversification
   - Avoid single-bucket concentration
   - Sensible balance across memory / substrate / socket.

7. Frequently asked

7.1 “Why not put memory megas at #1 if PER is single-digit?”

PER 5x looks like "trough PER,"
but a multiple built on "trough EPS" is dangerous.

The memory-cycle trap:
Cycle peak:      earnings spike → PER 5x
Cycle decline:   earnings cut in half → same price → PER 10x
Cycle trough:    earnings cut to 1/3 → same price → PER 15x+

So buying at PER 5x means:
- More cycle ahead → big gains
- Cycle turns → suddenly PER 15x at the same price → big losses

That's why memory investing is not
"how cheap does it look?"
but
"when does the cycle turn?"

To put memory at #1 here, you'd need separate proof on
HBM4 / HBM4E demand visibility, China demand recovery,
and the durability of AI capex.

This post does a clean side-by-side only —
so memory megas are placed mid-pack to reflect cycle-peak risk.

7.2 “Is Simmtech’s 20x PER real?”

Simmtech's 2027E PER 20.0x is consensus-based.

Conditional signals:
1. 2026 OP turns positive (from loss),
   producing a +1,234% optical YoY (it is base-effect, not the run rate)

2. 2027 OPM must expand beyond 8.6% for the 20x PER to be "real"

3. Need a higher share of AI memory module / SSD-controller
   substrate revenue → confirm margin mix improvement.

Risks:
- Margin recovery may lag consensus
- 8.6% OPM is among the lowest in substrates (vs Daeduck 15.5%)
- 1Q26 results could trigger consensus revisions.

Read:
20x PER is "potential" value, not yet realized value.
Margin recovery is the real test.
Wait for 1Q26 / 2Q26 confirmation before adding.

7.3 “Samsung E-M is a great company. Why is it #7?”

Samsung Electro-Mechanics fundamentals are among the best:
- Combined AI FC-BGA + MLCC + camera exposure
- 1Q26 OP +40% YoY
- Core node in the global AI parts supply chain.

But on price:
- 2026 YTD +296% (one of the biggest movers of the 11)
- 2026E PER 61.9x (heavy vs. bucket average)
- OPM 11.8% (FC-BGA alone is higher; cameras drag the blend).

The ranking is "attractiveness at current price,"
not "best long-term holding."

For a long-term core position, Samsung E-M ranks high.
For best value-for-growth at today's price, Daeduck and Simmtech lead.

8. How this links to other posts

Prior post (structure compare):
→ Substrate = "volume beta," test socket = "consumables beta"
→ Structural differences between the buckets.

This post (data compare):
→ Who is most attractive WITHIN each bucket
→ Not raw PER — "growth-adjusted multiple."

Macro-cycle synthesis post:
→ "Cycle before the stock"
→ Scale into these names after the macro gate clears.

KOSPI crash + macro-gate post:
→ After the May 15 -6.12% drop
→ Watch relative strength AND the macro gate
→ The framework used to select names here.

9. The one-line bottom line

Even among “AI back-end winners,” how much price has already done the work differs wildly. Low PER alone ≠ attractive. Low PER can mean “the market fears the cycle is topping” (memory) or “the market hasn’t bought in yet” (turnaround names).

Lined up in one table, the picture is clear. On a PER × OP-growth matrix, the sharpest setups are Simmtech, Daeduck Electronics, and Haesung DS. All three are substrate names — that is not an accident. Substrates are in the middle of a “shortage → ASP hike → margin expansion” cycle.

Within test sockets, LEENO Industrial is the quality leader but the multiple is full; ISC is the cleanest AI data-center beta but carries the tightest multiple. For best price-for-growth on a new entry, TSE is the value option.

Memory megas show stunning numbers but a cycle-peak debate at their core. SK hynix’s 2027E PER 5.2x would imply bankruptcy risk in a normal industry; in memory it means “the market doubts earnings durability.” If the cycle persists, the upside is huge; the moment it turns, the multiple expands automatically.

At today’s prices, the rational order for new capital is substrates > test sockets > memory megas. Within substrates, Daeduck Electronics (leadership premium) and Simmtech (turnaround value) are the cleanest. Whatever you choose, scale in only after the macro gate clears. Buying a great company at the right price is the actual job.

This article is research and commentary only and is not investment advice. Stock returns are per PyKRX, with 2025 returns from 2024 year-end close to 2025 year-end close, and 2026 YTD from the 2025 year-end close to the May 15 close. Operating-profit growth, PER, and operating margin are per the FnGuide CompanyGuide consensus (queried on May 15, 2026) and may differ from actual reported figures. The consensus reflects the market average and can differ from individual broker estimates, and may be revised. The PEG metric (PER ÷ growth) is a simplified valuation aid and is not sufficient by itself. The cycle-peak concern for memory megas is the author’s view; actual cycles can be longer or shorter than expected. The attractiveness ranking reflects “best at current price” and may differ from a “best long-term holding” ranking. Jeju Semiconductor is excluded from the direct comparison due to a lack of 2026–2027 consensus and warrants its own analysis. Global macro variables (US rates, oil, FX, VIX) can independently move the stocks. The analysis may be wrong. Data cut-off: May 15, 2026 close, KST.

Disclaimer: For research and information purposes only. Not investment advice. Names cited are for analytical illustration; readers should perform their own due diligence and consult licensed advisors before any investment decision.